Back contact type battery piece and photovoltaic module

Abstract

The invention relates to a back contact type battery piece and a photovoltaic module, which are applied to the field of photovoltaic power generation, the back contact type battery piece comprises a battery piece, a fixing piece, a welding strip and insulation paste, and the battery piece comprises positive electrode grid lines and negative electrode grid lines which are alternately arranged and arranged in parallel; the welding strips are arranged on the fixing piece in a reciprocating and penetrating manner, and each welding strip is used for connecting all the positive grid lines or all the negative grid lines on a single battery piece; when the welding strip is connected with the positive electrode grid line, the insulation paste coats the negative electrode grid line located below the covering position of the fixing piece. And when the welding strip is connected with the cathode grid line, the insulation paste coats the anode grid line below the covering position of the fixing piece. By adopting the scheme, the welding strip is connected with the positive grid line or the negative grid line through the position of the protruding fixing piece, so that the problems that in the prior art, the reliability is poor due to the fact that the welding strip is directly fixed to the battery piece in a dispensing mode, and glue films are prone to flowing into the position below the welding strip to cause pseudo soldering during lamination welding are solved; and the problem of high cost caused by fixing the welding strip and the battery piece by adopting a hot melt adhesive is also avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic cells, and in particular to a back-contact type cell sheet and a photovoltaic module. Background Art

[0002] Back-contact photovoltaic modules transfer the contact points (i.e., positive and negative electrodes) of the battery from the traditional front to the back. This design makes the front of the battery more complete and unobstructed, allowing it to receive more sunlight, thereby improving the photoelectric conversion efficiency. Existing back-contact photovoltaic modules are mainly designed with a main grid. Back-contact photovoltaic modules can also adopt a main grid-free design. The main grid-free back-contact battery eliminates the main grid and welding points, greatly reducing silver consumption, and has gradually become a research hotspot.

[0003] The main grid-free design of the back contact battery mainly adopts a staggered through-type design of positive and negative fine grids, and an insulating paste is used to insulate and protect one of the same-polarity grid lines (all positive fine grids or all negative fine grids) along the original main grid arrangement direction. Then, the welding strip is overlapped along the main grid direction and fixed on another same-level grid line. The main ways to fix the welding strip include direct coating technology, dispensing, etc. The direct coating technology is to use a hot melt adhesive film laid on the surface of the battery cell to fix the welding strip to the battery cell to form a battery string, and then the battery string is stacked, laminated, and other processes to form a component, but the use of hot melt film has the problem of high cost. The main process of fixing the solder ribbon by glue dispensing is to design the glue dispensing position on the battery cell, apply UV glue and place the solder ribbon, use ultraviolet lamp to cure the UV glue to fix the solder ribbon, and then use lamination welding to weld the solder ribbon to the battery cell. The main problems of this method are: first, the reliability of UV glue fixing the solder ribbon is poor, and the tension of the glue point is very small; second, there is easily glue film under the solder ribbon, which makes it easy for the glue film to flow into the solder ribbon position during the lamination process, resulting in component cold soldering. Summary of the invention

[0004] Based on this, a back-contact cell and photovoltaic module are provided to solve the problem of high cost caused by using hot-melt film when direct lamination technology is adopted in the prior art, or the problem of cold soldering caused by using UV glue when fixing solder strips by glue dispensing.

[0005] On the one hand, a back-contact type solar cell is provided, which is applied in the field of photovoltaic power generation, comprising:

[0006] A battery body, wherein the backlight surface of the battery body includes positive electrode grid lines and negative electrode grid lines which are alternately arranged and arranged in parallel;

[0007] A fixing piece, one side of which is provided with a first adhesive layer and is bonded to the battery body through the first adhesive layer;

[0008] Welding strips, which are reciprocatingly passed through the fixing member, and each welding strip is used to connect all positive grid lines or all negative grid lines on a single battery body;

[0009] Insulating glue, which is coated on the positive electrode grid wire or the negative electrode grid wire and used for insulation;

[0010] When the welding strip is connected to the positive grid line, the insulating glue is coated on the negative grid line below the covering position of the fixing part; when the welding strip is connected to the negative grid line, the insulating glue is coated on the positive grid line below the covering position of the fixing part.

[0011] Based on the above technical solution, the present invention can also be improved as follows.

[0012] In one implementation, the fixing member includes:

[0013] The middle base,

[0014] A first adhesive layer, the first adhesive layer is located on one side of the intermediate base layer and is used for bonding with the battery body;

[0015] The second adhesive coating layer is located on the other side of the middle base layer and is used for bonding with the upper adhesive film.

[0016] In one implementation, the fixing member includes:

[0017] The welding belt hole is used for the reciprocating insertion of the welding belt, and a plurality of welding belt holes are provided.

[0018] In one implementation, the fixing member further includes:

[0019] Laser holes, where the laser holes and the welding strip holes are alternately opened, and the laser holes are used to weld the welding strip to the positive electrode grid line or the negative electrode grid line by laser;

[0020] When the welding strip is connected to the positive grid line, the laser holes at least correspond to the positive grid lines one by one; when the welding strip is connected to the negative grid line, the laser holes at least correspond to the negative grid lines one by one.

[0021] In one implementation, the welding hole is a flat hole, and the laser hole is a round hole or an elliptical hole.

[0022] In one implementation, the width of the laser hole is not less than the width of the welding ribbon hole;

[0023] and / or, the length of the laser hole is not less than the length of the welding strip hole;

[0024] The width direction is the direction in which the welding strip is passed through, and the length direction is the direction perpendicular to the direction in which the welding strip is passed through.

[0025] In one implementation, the positive grid lines and the negative grid lines are evenly spaced, and the welding holes and the laser holes are evenly alternately arranged;

[0026] When the welding strip is connected to the positive grid line, the laser hole corresponds to the positive grid line one by one, and the welding strip hole is located between two adjacent positive grid lines; when the welding strip is connected to the negative grid line, the laser hole corresponds to the negative grid line one by one, and the welding strip hole is located between two adjacent negative grid lines;

[0027] Alternatively, the welding strip is connected to the positive grid line or the negative grid line, the laser holes correspond to the positive grid lines and the negative grid lines one by one, and the welding strip holes are located between adjacent positive grid lines and negative grid lines.

[0028] In one implementation, there are multiple welding ribbons which are arranged parallel to each other;

[0029] There is one fixing piece, and a plurality of rows of through holes are arranged on the fixing piece, the number of rows of through holes is the same as the number of solder strips, and each row of through holes includes laser holes and solder strip holes arranged alternately;

[0030] Alternatively, there are multiple fixing members, one fixing member corresponds to one welding strip, each fixing member is provided with a row of through holes, and each row of through holes includes laser holes and welding strip holes that are alternately arranged.

[0031] In one implementation, the battery body further includes:

[0032] A left grid line, which is located at one side of the battery body and is used to connect one end of all positive grid lines and does not contact the negative grid line;

[0033] The right grid line is located at the other side of the battery body, and is used to connect one end of all the negative grid lines and does not contact the positive grid line;

[0034] The left grid line is arranged in parallel with the right grid line, and the left grid line and the positive grid line are perpendicular to each other.

[0035] In another aspect, the present invention further provides a photovoltaic module, which, in one implementation, includes a plurality of back-contact cells.

[0036] The beneficial effects of the present invention are as follows: a fixing piece is provided to wind the welding strip, and then the fixing piece is fixed to the battery body through a first adhesive coating layer, thereby fixing the position of the welding strip on the battery body. At this time, since the welding strip is reciprocatedly passed through the fixing piece, it is convenient for the welding strip to protrude from the fixing piece at the position where it needs to be connected to the positive grid line or the negative grid line, so that the welding strip will connect to the positive grid line or the negative grid line through the position of the protruding fixing piece, thereby avoiding the poor reliability caused by directly fixing the welding strip on the battery body in a dispensing manner in the prior art, and the problem that the adhesive film is easy to flow under the welding strip during lamination welding to cause a cold weld, and also avoiding the high cost problem caused by using hot melt adhesive to fix the welding strip and the battery body; in addition, since an insulating adhesive is provided, the insulating adhesive is used to align the welding strip under the fixing piece and does not need to be fixed The positive grid line or the negative grid line connected to the welding strip on the fixture is coated to insulate and isolate any one of the positive grid line or the negative grid line, thereby improving the stability when welding the welding strip. Since the width of the fixing member is larger than the welding strip in actual use, when the insulating glue is used to coat the target grid line, only the target grid line covered by the local position or the whole position in the width direction of the fixing member can be coated. For example, the target grid line covered by the width direction of the fixing member is fully coated with the insulating glue, so that the welding strip and the target grid line that is not welded can be separated; or the range of coating the insulating glue on the target grid line is set to that the size coated along the width direction of the welding strip is 1.2 times to 1.5 times the width of the welding strip, and the size of the welding strip protruding on both sides of the insulating glue on the target grid line is equal, thereby ensuring the isolation effect between the welding strip and the target grid line. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of the structure of a back-contact type battery cell in one embodiment;

[0038] Figure 2 for Figure 1 The schematic diagram of the structure after the enlargement of A in the middle;

[0039] Figure 3 for Figure 1 The schematic diagram of the structure after enlargement at B in the middle;

[0040] Figure 4 A schematic diagram of the structure of a cross section of a back-contact type battery sheet during installation in one embodiment;

[0041] Figure 5 for Figure 4 The schematic diagram of the structure after enlargement at C in the middle;

[0042] Figure 6 It is a structural schematic diagram of a cross section of a fixing member in an embodiment;

[0043] Figure 7 It is a schematic diagram of the length direction structure of the fixing member in the embodiment;

[0044] Figure 8 Schematic diagram of the structure of welding ribbon hole and laser hole.

[0045] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0046] 10. Battery body; 11. Positive grid line; 12. Negative grid line; 13. Left grid line; 14. Right grid line; 15. Positioning part;

[0047] 20. welding strip; 21. first raised portion; 22. second raised portion;

[0048] 30. Fixing piece; 31. Welding hole; 32. Laser hole; 33. First adhesive layer; 34. Intermediate base layer; 35. Second adhesive layer. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with 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.

[0050] See also Figure 1 A back-contact cell refers to a photovoltaic module in which the electrode grid lines of the cell body 10 are all located on the back of the cell body 10, forming a cross-back-contact structure. This design makes the front of the photovoltaic module completely unobstructed, and light can directly irradiate the active area of ​​the cell body 10, thereby maximizing the photoelectric conversion efficiency. This application elaborates on the structure of the back-contact cell.

[0051] A back contact battery cell, see Figure 1 , Figure 2 and Figure 4 , applied to the field of photovoltaic power generation, comprising a battery body 10, a fixing part 30, a welding strip 20 and an insulating glue, wherein the backlight surface of the battery body 10 comprises positive grid lines 11 and negative grid lines 12 which are alternately arranged and arranged in parallel; a first glue layer 33 is provided on one side of the fixing part 30, and the fixing part 30 is bonded to the battery body 10 through the first glue layer 33; the welding strip 20 is reciprocatedly passed through the fixing part 30, and each welding strip 20 is used to connect all the positive grid lines 11 or all the negative grid lines 12 on a single battery body 10; the insulating glue is coated on the positive grid lines 11 or the negative grid lines 12 and used for insulation; when the welding strip 20 is connected to the positive grid lines 11, the insulating glue is coated on the negative grid lines 12 located below the covering position of the fixing part 30; when the welding strip 20 is connected to the negative grid lines 12, the insulating glue is coated on the positive grid lines 11 located below the covering position of the fixing part 30.

[0052] Using the above solution, see Figure 4, by setting a fixing piece 30 to wrap the welding tape 20, and then fixing the fixing piece 30 on the battery body 10 through the first adhesive coating layer 33, so as to fix the position of the welding tape 20 on the battery body 10. At this time, since the welding tape 20 is reciprocatedly passed through the fixing piece 30, it is convenient for the welding tape 20 to be connected with the positive grid line 11 or the negative grid line 12 at the position protruding from the fixing piece 30, so that the welding tape 20 will be connected to the positive grid line 11 or the negative grid line 12 through the position protruding from the fixing piece 30, thereby avoiding the poor reliability caused by directly fixing the welding tape 20 on the battery body 10 in the prior art by dispensing glue, and the problem that the adhesive film is easy to flow under the welding tape 20 during lamination welding to cause a cold weld, and also avoiding the high cost problem caused by using hot melt adhesive to fix the welding tape 20 and the battery body 10; in addition, since an insulating glue is provided, the insulating glue is used to align the welding tape 20 located below the fixing piece 30 and does not need to be passed through the fixing piece 30. The positive grid line 11 or the negative grid line 12 connected to the welding strip 20 on the fixing member 30 is coated to insulate and isolate any one of the positive grid line 11 or the negative grid line 12, thereby improving the stability when welding the welding strip 20. Since the width of the fixing member 30 is larger than the welding strip 20 in actual use, when the insulating glue is used to coat the target grid line, only the target grid line covered by the local position or the entire position in the width direction of the fixing member 30 can be coated. For example, the target grid line covered by the width direction of the fixing member 30 is fully coated with the insulating glue, so that the welding strip 20 and the target grid line that is not welded can be separated; or the range of coating the insulating glue on the target grid line is set to a size coated along the width direction of the welding strip 20 that is 1.2 times to 1.5 times the width of the welding strip 20, and the size of the insulating glue protruding from the welding strip 20 on both sides of the target grid line is equal, thereby ensuring the isolation effect of the welding strip 20 and the target grid line.

[0053] The above-mentioned “target grid line” means the grid line that is not welded to the welding strip 20 . For example, when the welding strip 20 is used to weld the positive grid line 11 , the target grid line is the negative grid line 12 ; when the welding strip 20 is used to weld the negative grid line 12 , the target grid line is the positive grid line 11 .

[0054] For details, see Figure 4 After being applied, the insulating glue is cured at high temperature and has good stability and temperature resistance. Therefore, even if lamination or laser welding is used later, the insulating glue will not melt, that is, the insulating glue will not flow under the welding strip 20 and will not affect the welding position of the welding strip 20.

[0055] For details, see Figure 1 and Figure 4Since the positive grid lines 11 and the negative grid lines 12 are arranged in parallel, and one welding strip 20 needs to connect all the positive grid lines 11 or negative grid lines 12, the welding strip 20 is reciprocatedly passed through the fixing member 30, and the fixing member 30 is bonded to the battery body 10. Therefore, the fixing member 30 needs to be set at a certain angle with the positive grid lines 11, and similarly, the fixing member 30 also needs to be set at a certain angle with the negative grid lines 12, so that the welding strip 20 can simultaneously connect all the positive grid lines 11 or negative grid lines 12 on a battery body 10. Optionally, the fixing member 30 can be set perpendicular to the positive grid lines 11 and the negative grid lines 12 to reduce the length of the welding strip 20 and simplify the coating range of the insulating glue.

[0056] In some embodiments, see Figure 6 The fixing member 30 includes: an intermediate base layer 34, a first adhesive layer 33 and a second adhesive layer 35. The first adhesive layer 33 is located on one side of the intermediate base layer 34 and is used to bond with the battery body 10; the second adhesive layer 35 is located on the other side of the intermediate base layer 34 and is used to bond with the upper adhesive film. In this way, the fixing member 30 is set as a three-layer structure, the main body of the fixing member 30 is formed by the intermediate base layer 34, and the fixing member 30 is pasted on the battery body 10 by the first adhesive layer 33, so as to fix the relative position of the welding strip 20 and the battery body 10, so as to help the welding strip 20 and the corresponding positive electrode grid line 11 to be closely attached, or to help the welding strip 20 and the corresponding negative electrode grid line 12 to be closely attached; the adhesive film located on the upper side is bonded by the second adhesive layer 35.

[0057] For details, see Figure 4 and Figure 6 , the first glue layer 33 and the second glue layer 35 are respectively located on both sides of the middle base layer 34, and the two glue layers can be glue applied later. For example, the welding tape 20 can be first inserted into the fixing part 30, and then the first glue layer 33 is applied to the side of the fixing part 30 facing the battery body 10 to help the fixing part 30 to be tightly attached to the battery body 10, so as to preliminarily fix the position of the welding tape 20 and the battery body 10; when applying the second glue layer 35, the welding tape 20 can also be first inserted into the fixing part 30 back and forth and then applied; or, the welding tape 20 can be first inserted into the fixing part 30, and then the first glue layer 33 can be applied to the fixing part 30, and then the fixing part 30 can be fixed on the battery body 10 through the first glue layer 33, and the welding tape 20 and the battery body 10 are welded or laminated, and then the second glue layer 35 is applied.

[0058] In the embodiments, see Figure 6Since the first coating layer 33 is a coating layer and a temperature-resistant glue such as 150°C is selected, the coating layer will not flow into the bottom of the welding strip 20 during lamination, thus ensuring the stability of the connection position between the welding strip 20 and the battery body 10 during lamination and avoiding the occurrence of cold solder joints. The intermediate base layer 34 can be any one of PET, PC and PS, and the first coating layer 33 and the second coating layer 35 can be any one of acrylate glue, epoxy resin glue and organic silicone glue.

[0059] In some embodiments, see Figure 7 The fixing member 30 includes a welding belt hole 31, which is used for the reciprocating penetration of the welding belt 20, and a plurality of welding belt holes 31 are provided. In this way, the welding belt hole 31 is provided, so that the welding belt 20 can be penetrated back and forth on the fixing member 30, and the penetration position of the welding belt 20 can be positioned. After the welding belt 20 is penetrated on the fixing member 30, along the length direction of the fixing member 30, the welding belt 20 is wavy, so that only the position on the welding belt 20 that matches the positive grid line 11 or the negative grid line 12 protrudes from the fixing member 30, so that the welding belt 20 is easy to abut against the position where the positive grid line 11 or the negative grid line 12 needs to be welded, so as to facilitate the welding of the welding belt 20.

[0060] For details, see Figure 4 and Figure 5 The welding strip 20 is passed back and forth on the fixing member 30, so that multiple positions in the length direction of the fixing member 30 are provided with protruding welding strips 20. When the welding strip 20 is used to connect the positive electrode grid lines 11 on the battery body 10, the protruding position of the welding strip 20 on the fixing member 30 is not less than the number of the positive electrode grid lines 11 on the battery body 10, and the protruding welding strip 20 and the positive electrode grid lines 11 form a one-to-one correspondence and fit relationship, so as to facilitate connecting all the positive electrode grid lines 11 through the welding strip 20; when the welding strip 20 is used to connect the negative electrode grid lines 12 on the battery body 10, the protruding position of the welding strip 20 on the fixing member 30 is not less than the number of the negative electrode grid lines 12 on the battery body 10, and the protruding position of the welding strip 20 on the fixing member 30 is not less than the number of the negative electrode grid lines 12 on the battery body 10, and the protruding position of the welding strip 20 and the negative electrode grid lines 12 form a one-to-one correspondence and fit relationship, so as to facilitate connecting all the negative electrode grid lines 12 through the welding strip 20.

[0061] When only the welding tape hole 31 is provided on the fixing member 30 , the welding tape 20 can be welded to the corresponding position on the battery body 10 by lamination welding; or the welding tape 20 can be welded to the corresponding position on the battery body 10 by laser welding.

[0062] Specifically, the fixing member 30 is a narrow strip structure, or the fixing member 30 can also be a wider strip structure. The fixing member 30 is provided with alternately arranged welding tape holes 31 and laser holes 32. The welding tape holes 31 and laser holes 32 extending along the same length direction and alternately arranged are a group of welding auxiliary holes. At least one group of welding auxiliary holes can be set on each fixing member 30, and each group of welding auxiliary holes is used to connect a welding tape 20. Therefore, only one welding tape 20 can be passed through each fixing member 30, or multiple welding tapes 20 can be passed through each fixing member 30, which is beneficial to reduce the number of fixing members 30.

[0063] In some embodiments, see Figure 7 The fixing member 30 also includes: laser holes 32, which are alternately opened with the welding tape holes 31, and the laser holes 32 are used to weld the welding tape 20 to the positive electrode grid line 11 or the negative electrode grid line 12 by laser; when the welding tape 20 is connected to the positive electrode grid line 11, the laser holes 32 at least correspond to the positive electrode grid line 11; when the welding tape 20 is connected to the negative electrode grid line 12, the laser holes 32 at least correspond to the negative electrode grid line 12. In this way, since the laser holes 32 and the welding strip holes 31 are opened alternately, the laser holes 32 are arranged between adjacent welding strip holes 31, so that the opening position of the laser holes 32 corresponds to the position where the welding strip 20 protrudes from the fixing part 30, and thus, the welding strip 20 can be welded by laser from the laser hole 32, and the welding strip 20 located on one side of the fixing part 30 is laser welded through the laser hole 32, so that the welding strip 20 is fixed on the corresponding positive grid line 11 or the negative grid line 12; specifically, when the welding strip 20 is used to connect the positive grid line 11, the laser holes 32 correspond to the positive grid line 11 one by one, so that it is convenient to weld the positive grid line 11 and the welding strip 20 together from the laser hole 32; when the welding strip 20 is used to connect the negative grid line 12, the laser holes 32 correspond to the negative grid line 12 one by one, so that it is convenient to weld the negative grid line 12 and the welding strip 20 together from the laser hole 32.

[0064] Specifically, the positive grid lines 11 and the negative grid lines 12 can be arranged at equal intervals, and the distance between adjacent laser holes 32 is equal to the distance between adjacent positive grid lines 11 and negative grid lines 12. Therefore, the position of the laser hole 32 can completely correspond to the position of the positive grid lines 11 or the negative grid lines 12, so that when laser welding is performed, it can be ensured that the welding strip 20 is welded to the corresponding positive grid lines 11 or negative grid lines 12, so as to accurately complete the welding of the welding strip 20.

[0065] In some embodiments, see Figure 7, the welding hole 31 is a flat hole, and the laser hole 32 is a round hole or an elliptical hole. In this way, the welding hole 31 is set as a flat hole, which is convenient for the welding belt 20 to penetrate, and can play a positioning effect on the angle of the welding belt 20; the flat hole can also play a role in reducing the bending of the welding belt 20, thereby effectively avoiding the local excessive stress or fracture of the welding belt 20 caused by bending; the laser hole 32 is set as a larger hole, such as a round hole or an elliptical hole, so that it is convenient for the laser to pass through and perform welding during laser welding.

[0066] When used specifically, it is sufficient to set the circular hole or elliptical hole as a wide hole with a certain length and width, so as to facilitate the laser to pass through and weld. Therefore, the laser hole 32 can be not only a circular hole or an elliptical hole, but also a square hole, etc.

[0067] In some embodiments, the width of the laser hole 32 is not less than the width of the welding tape hole 31; and / or the length of the laser hole 32 is not less than the length of the welding tape hole 31; wherein the width direction is the direction in which the welding tape is inserted, and the length direction is the direction perpendicular to the direction in which the welding tape is inserted. In this way, the size of the laser hole 32 and the welding tape hole 31 is reasonably set, which facilitates the welding tape 20 to be inserted back and forth in the multiple welding tape holes 31, and improves the stability of the welding tape 20 when being inserted.

[0068] In some embodiments, the positive grid lines 11 and the negative grid lines 12 are evenly spaced, and the welding tape holes 31 and the laser holes 32 are evenly alternately arranged; when the welding tape 20 is connected to the positive grid lines 11, the laser holes 32 correspond to the positive grid lines 11 one by one, and the welding tape holes 31 are located between two adjacent positive grid lines 11; when the welding tape 20 is connected to the negative grid lines 12, the laser holes 32 correspond to the negative grid lines 12 one by one, and the welding tape holes 31 are located between two adjacent negative grid lines 12; or, the welding tape 20 is connected to the positive grid lines 11 or the negative grid lines 12, the laser holes 32 correspond to the positive grid lines 11 and the negative grid lines 12 one by one, and the welding tape holes 31 are located between the adjacent positive grid lines 11 and the negative grid lines 12. In this way, when the welding strip 20 is used to connect the positive electrode grid line 11, since the insulating glue is applied on the negative electrode grid line 12 located below the fixing member 30, it is only necessary to set the welding strip hole 31 between two adjacent positive electrode grid lines 11; similarly, when the welding strip 20 is used to connect the negative electrode grid line 12, since the insulating glue is applied on the positive electrode grid line 11 located below the fixing member 30, it is only necessary to set the welding strip hole 31 between two adjacent negative electrode grid lines 12.

[0069] In some embodiments, there are multiple solder strips 20 and they are arranged in parallel with each other; there is one fixing member 30, and multiple rows of through holes are arranged on the fixing member 30, the number of rows of through holes is the same as the number of solder strips 20, and each row of through holes includes laser holes 32 and solder strip holes 31 arranged alternately; or, there are multiple fixing members 30, one fixing member 30 corresponds to one solder strip 20, and each fixing member 30 is provided with a row of through holes, and each row of through holes includes laser holes 32 and solder strip holes 31 arranged alternately. In this way, when the solder strip 20 and the fixing member 30 are connected together, the fixing member 30 and the solder strip 20 can be in a one-to-one correspondence, and multiple solder strips 20 can also be passed through one fixing member 30, thereby improving the integration of the overall structure.

[0070] In the embodiments, see Figure 1 , Figure 2 and Figure 3 The battery body 10 further includes a positioning portion 15, which is disposed on one side of the battery body 10 and is used to guide the direction in which the welding strip 20 extends out of the battery body 10. In this way, since the welding strip 20 needs to extend out of the battery body 10, it is necessary to locate which end of the battery body 10 the welding strip 20 extends from, so as to determine the correct laying direction of the welding strip 20; the positioning portion 15 is provided to facilitate guiding the placement position of the welding strip 20 when laying the fixing member 30 and the welding strip 20, so as to avoid the welding strip 20 being placed upside down.

[0071] For details, see Figure 1 , Figure 2 and Figure 3 When laying the positioning portion 15 and the welding strip 20, the power of the battery body 10 needs to be led out, so the positioning portion 15 can be used to locate the direction of the lead-out; when in use, the positioning portion 15 can be set on one side of the battery body 10 and the side is parallel to the positive grid line 11 and the negative grid line 12. When the welding strip 20 extends in a direction perpendicular to the positive grid line 11 and the negative grid line 12, that is, the side is perpendicular to the welding strip 20. Therefore, the positioning portion 15 can be set on the side to indicate the direction in which the welding strip 20 extends out of the battery, such as setting one end of the positioning portion 15 as the direction in which the welding strip 20 connected to the positive grid line 11 extends, and correspondingly, the end opposite to the positioning portion 15 is the direction in which the welding strip 20 connected to the negative grid line 12 extends; the direction setting can also be reversed, as long as it can position the direction in which the welding strip 20 extends out.

[0072] In the embodiments, see Figure 1 , Figure 2 and Figure 3The positioning part 15 is arranged at both ends of one side of the battery body 10 and each end is provided with a triangular notch. In this way, the positioning part 15 is arranged on the side of the battery body 10, which has a positioning effect while reducing the right angles of the edge of the battery body 10, protecting the operator and avoiding bending or other damage to the battery body 10 caused by arranging the positioning part 15 in the middle of the battery body 10.

[0073] For details, see Figure 1 , Figure 2 and Figure 3 The battery body 10 is rectangular and has two notches on one side thereof. The side is parallel to the positive electrode grid line 11 and the negative electrode grid line 12. The two notches are symmetrically arranged along the length direction of the grid lines and are respectively arranged at both ends of the side.

[0074] In the embodiments, see Figure 4 The positive grid lines 11 and the negative grid lines 12 are evenly spaced, and the welding strips 20 are provided in multiple numbers and are arranged in parallel with each other. In this way, the placement of the welding strips is convenient, and the way of connecting the welding strips 20 to the positive grid lines 11 or the negative grid lines 12 is simplified.

[0075] Specifically, the welding strip 20 is divided into a first welding strip and a second welding strip. The first welding strip is used to connect all the positive grid lines 11 on a single battery body 10, and the second welding strip is used to connect all the negative grid lines 12 on a single battery body 10. There are multiple first welding strips and second welding strips that are arranged parallel to each other. By setting up a plurality of first welding strips and connecting the first welding strips to all positive grid lines 11 on a single battery body 10, and by setting up a plurality of second welding strips and connecting the second welding strips to all negative grid lines 12 on a single battery body 10, that is, by setting up a plurality of first welding strips and second welding strips to connect the battery body 10, the following effects are achieved: improving the shunt effect, for the positive grid lines 11 and the negative grid lines 12, respectively setting up a plurality of connected welding strips 20 can disperse and derive the current, reduce the current density of a single welding strip 20, thereby reducing resistance loss and heat generation; improving the reliability of the photovoltaic battery body 10, even if a certain welding strip 20 is broken or has poor contact, other welding strips 20 can still continue to derive current, thereby improving the overall reliability of the system; facilitating assembly and maintenance, the design of multiple welding strips 20 makes the assembly and maintenance of photovoltaic battery components more convenient and flexible; enhancing the mechanical strength, the connection between the welding strip 20 and the grid line not only plays a conductive role, but the welding strip 20 can also serve as a reinforcing rib to improve the structural stability of the battery body 10.

[0076] Specifically, when arranging a plurality of first welding strips and a plurality of second welding strips, since the first welding strips and the second welding strips are arranged in parallel, the positions of the first welding strips and the second welding strips can be set according to requirements. The following describes possible arrangements of the first welding strips and the second welding strips:

[0077] The first type is to arrange all the first welding strips adjacent to each other, and to arrange all the second welding strips adjacent to each other. Since "when the welding strip 20 is connected to the positive grid line 11, the insulating glue is applied to the negative grid line 12 below the covering position of the fixing member 30; when the welding strip 20 is connected to the negative grid line 12, the insulating glue is applied to the positive grid line 11 below the covering position of the fixing member 30", this arrangement of the first welding strip and the second welding strip can conveniently improve the efficiency of applying the insulating glue, such as effectively avoiding the insulating lateral glue that needs to cover the positive grid line 11 from extending to the position of the negative grid line 12;

[0078] Secondly, the first welding strips and the second welding strips may be arranged alternately.

[0079] In the embodiments, see Figure 1 The number of the first welding strips and the number of the second welding strips can be set to be equal, for example, the number of each welding strip 20 can be between 5 and 10.

[0080] In some embodiments, see Figure 1 The battery body 10 further includes a left grid line 13 and a right grid line 14. The left grid line 13 is located at one side of the battery body 10. The left grid line 13 is used to connect one end of all the positive grid lines 11 and does not contact the negative grid line 12. The right grid line 14 is located at the other side of the battery body 10. The right grid line 14 is used to connect one end of all the negative grid lines 12 and does not contact the positive grid line 11. The left grid line 13 and the right grid line 14 are arranged in parallel, and the left grid line 13 and the positive grid line 11 are perpendicular to each other. In this way, the battery body 10 is provided with a left grid line 13 and a right grid line 14. The left grid line 13 is used to connect one end of all the positive grid lines 11, and the right grid line 14 is used to connect one end of all the negative grid lines 12. The left grid line 13 and the right grid line 14 are used to converge, that is, the left grid line 13 converges all the positive grid lines 11, and the right grid line 14 converges all the negative grid lines 12, so as to prevent current mismatch.

[0081] A photovoltaic module comprises a plurality of back-contact type cells.

[0082] For the back-contact battery cell of the present application, there are at least two welding methods when fixing the welding ribbon 20 and the battery body 10 together, including laser welding and lamination welding. The following specifically describes the two welding methods.

[0083] Embodiment 1:

[0084] When laser welding is used in this application, see Figure 1 and Figure 4The photovoltaic module includes a battery body 10, a welding strip 20, a fixing member 30 and an insulating glue. The battery body 10 includes positive grid lines 11 and negative grid lines 12 arranged alternately and in parallel. The fixing member 30 is provided with welding strip holes 31 and laser holes 32 arranged alternately. The welding strip holes 31 are used to facilitate the passing of the welding strip 20 and fix the position of the welding strip 20. The laser holes 32 are used to facilitate the passing of the laser and facilitate the welding strip 20 and the positive grid line 11 or the welding strip 20 and the negative grid line 12. Welding; when using laser welding, it is best to meet the requirements of "the positive grid lines 11 and the negative grid lines 12 are arranged at equal intervals, the distance between adjacent laser holes 32 is equal to the distance between adjacent positive grid lines 11 and negative grid lines 12; the laser hole 32 is used to weld the welding strip 20 to the positive grid lines 11 or the negative grid lines 12 by laser", thereby simplifying the setting of the positions of the welding strip holes 31 and the laser holes 32, and it is only necessary to set the welding strip holes 31 and the laser holes 32 at equal intervals to meet the requirements.

[0085] For the above structure, when using it, see Figure 4 and Figure 5 When the first welding tape is used to connect the positive grid line 11, the first welding tape is passed back and forth in the welding tape hole 31, so that the first welding tape is arranged in a wavy shape relative to the fixing member 30, and the first welding tape forms a first protrusion 21 and a second protrusion 22 on both sides of the fixing member 30, respectively, and the first protrusion 21 and the second protrusion 22 arranged along the length direction are alternately arranged, wherein the first protrusion 21 is used to fit with the positive grid line 11, and the second protrusion 22 is located on the side of the fixing member 30 facing away from the battery body 10, and the first protrusion 21 and the second protrusion 22 are arranged on the fixing member The positions extending on 30 all coincide with the laser holes 32. During laser welding, the first protrusion 21 is welded by passing the welding laser through the laser holes 32 corresponding to the first protrusion 21, so as to weld the first protrusion 21 to the positive electrode grid line 11. It can also be seen from the above that among any two adjacent laser holes 32, only one laser hole 32 is used for the laser to pass through. Therefore, when setting the positional relationship between the welding tape hole 31 and the laser hole 32, it is also possible not to set the laser hole 32 corresponding to the second protrusion 22. This setting reduces the position of the laser hole 32 by half.

[0086] Correspondingly, when the second welding tape is used to connect the negative electrode grid line 12, the second welding tape also has corresponding third and fourth raised portions, wherein the third raised portion corresponds to the first raised portion 21, and the fourth raised portion corresponds to the second raised portion 22. Therefore, the understanding of the third and fourth raised portions and the operation during laser welding can refer to the above-mentioned first and second raised portions 21, 22, and will not be repeated here.

[0087] Embodiment 2:

[0088] When lamination welding is used in this application, refer to Figure 1 and Figure 7 The photovoltaic module includes a battery body 10, a welding strip 20, a fixing part 30 and an insulating adhesive. The battery body 10 includes positive grid lines 11 and negative grid lines 12 that are alternately arranged and arranged in parallel. The fixing part 30 is provided with evenly arranged welding strip holes 31. The welding strip holes 31 are used to facilitate the passage of the welding strip 20 and fix the position of the welding strip 20. Since the laser hole 32 is not required for lamination welding, whether the laser hole 32 is provided on the fixing part 30 has no effect when used for lamination welding; however, if the laser hole 32 is provided, the laser hole 32 can be used to assist in viewing whether the welding strip 20 is placed correctly and whether the welding strip 20 is in contact with the corresponding positive grid line 11 or negative grid line 12. Since the welding strip 20 is passed back and forth on the fixing part 30, after the welding strip 20 is wrapped around the fixing part 30, the preparatory operations before lamination welding include:

[0089] See also Figure 4 and Figure 5 When the first welding tape is used to connect the positive grid line 11, the first welding tape is passed back and forth in the welding tape hole 31, so that the first welding tape is arranged in a wave shape relative to the fixing member 30, and the first welding tape forms a first protrusion 21 and a second protrusion 22 on both sides of the fixing member 30, respectively, and the first protrusion 21 and the second protrusion 22 are alternately arranged along the length direction, wherein the first protrusion 21 is used to fit with the positive grid line 11, and the second protrusion 22 is located on the side of the fixing member 30 facing away from the battery body 10. When laminating welding is performed, it is ensured that all the first protrusions 21 are aligned with the positive grid line 11, so that the laminating welding can be performed, thereby fixing the first welding tape on the positive grid line 11;

[0090] Correspondingly, when the second welding tape is used to connect the negative electrode grid line 12, the second welding tape also has corresponding third and fourth protrusions, wherein the third protrusion corresponds to the first protrusion 21, and the fourth protrusion corresponds to the second protrusion 22. Therefore, the understanding of the third and fourth protrusions and the operation during lamination welding can refer to the above; that is, by passing the second welding tape back and forth in the welding tape hole 31, the second welding tape is arranged in a wavy shape relative to the fixing member 30, and the second welding tape forms a third protrusion and a fourth protrusion on both sides of the fixing member 30, respectively, and the third and fourth protrusions are alternately arranged along the length direction, wherein the third protrusion is used to fit with the negative electrode grid line 12, and the fourth protrusion is located on the side of the fixing member 30 facing away from the battery body 10. When lamination welding is performed, ensure that all the third protrusions are aligned with the negative electrode grid line 12 to perform lamination welding, thereby fixing the second welding tape on the negative electrode grid line 12.

[0091] In the embodiment, laser welding requires the use of laser, so the welding strip 20 can use a high-temperature welding strip 20, and the adhesive film can use a conventional adhesive film; the lamination welding can be lamination low-temperature welding, and the lamination low-temperature welding needs to match the low-temperature welding strip 20, and the adhesive film is also a conventional adhesive film. During the lamination process, the low-temperature welding strip 20 is alloyed with the metal grid line for welding.

[0092] In the embodiments, see Figure 7 and Figure 8 The sizes of the laser hole 32 and the soldering tape hole 31 on the fixing member 30 correspond to the sizes of the soldering tape 20. Specifically, the length of the laser hole 32 is a and the width is b, and the length of the soldering tape hole 31 is c and the width is d. The relationship may be: a≥c, b≥d, c>the width of the soldering tape, d>the thickness of the soldering tape.

[0093] It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner. Therefore, the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0094] The structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0095] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0096] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0097] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0098] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0099] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0100] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A back-contact cell, used in the field of photovoltaic power generation, characterized in that: include: A battery body (10), wherein the backlight surface of the battery body (10) comprises positive electrode grid lines (11) and negative electrode grid lines (12) which are alternately arranged and arranged in parallel; A fixing member (30), wherein a first adhesive layer (33) is provided on one side of the fixing member (30), and the fixing member (30) is bonded to the battery body (10) via the first adhesive layer (33); A welding strip (20), the welding strip (20) being reciprocatingly inserted on the fixing member (30), each welding strip (20) being used to connect all the positive electrode grid lines (11) or all the negative electrode grid lines (12) on the battery body (10); Insulating glue, the insulating glue is coated on the positive electrode grid line (11) or the negative electrode grid line (12) and is used for insulation; When the welding strip (20) is connected to the positive grid line (11), the insulating glue is coated on the negative grid line (12) located below the covering position of the fixing member (30); when the welding strip (20) is connected to the negative grid line (12), the insulating glue is coated on the positive grid line (11) located below the covering position of the fixing member (30).

2. The back contact type battery sheet according to claim 1, characterized in that: The fixing member (30) comprises: Intermediate base layer (34), The first adhesive layer (33), the first adhesive layer (33) is located on one side of the intermediate base layer (34) and is used for bonding with the battery body (10); A second adhesive coating layer (35), the second adhesive coating layer (35) is located on the other side of the intermediate base layer (34) and is used for bonding with the upper adhesive film.

3. The back contact type battery sheet according to claim 1, characterized in that: The fixing member (30) comprises: A welding belt hole (31), wherein the welding belt hole (31) is used for the reciprocating insertion of the welding belt (20), and a plurality of welding belt holes (31) are provided.

4. The back contact type battery sheet according to claim 3, characterized in that: The fixing member (30) further comprises: Laser holes (32), the laser holes (32) and the welding strip holes (31) being alternately provided, the laser holes (32) being used to weld the welding strip (20) onto the positive electrode grid line (11) or the negative electrode grid line (12) by laser welding; When the welding strip (20) is connected to the positive electrode grid line (11), the laser hole (32) corresponds to at least one of the positive electrode grid line (11); when the welding strip (20) is connected to the negative electrode grid line (12), the laser hole (32) corresponds to at least one of the negative electrode grid line (12).

5. The back contact type battery sheet according to claim 4, characterized in that: The welding strip hole (31) is a flat hole, and the laser hole (32) is a round hole or an elliptical hole.

6. The back contact type battery sheet according to claim 5, characterized in that: The width of the laser hole (32) is not less than the width of the welding strip hole (31); and / or, the length of the laser hole (32) is not less than the length of the welding strip hole (31); The width direction is the direction in which the welding strip is passed through, and the length direction is a direction perpendicular to the direction in which the welding strip is passed through.

7. The back contact type battery sheet according to any one of claims 4 to 6, characterized in that: The positive electrode grid lines (11) and the negative electrode grid lines (12) are evenly spaced, and the welding strip holes (31) and the laser holes (32) are evenly and alternately arranged; When the welding strip (20) is connected to the positive electrode grid line (11), the laser hole (32) corresponds to the positive electrode grid line (11) one by one, and the welding strip hole (31) is located between two adjacent positive electrode grid lines (11); when the welding strip (20) is connected to the negative electrode grid line (12), the laser hole (32) corresponds to the negative electrode grid line (12) one by one, and the welding strip hole (31) is located between two adjacent negative electrode grid lines (12); Alternatively, the welding strip (20) is connected to the positive electrode grid line (11) or the negative electrode grid line (12), the laser holes (32) correspond to the positive electrode grid lines (11) and the negative electrode grid lines (12) one by one, and the welding strip holes (31) are located between adjacent positive electrode grid lines (11) and negative electrode grid lines (12).

8. The back contact type battery sheet according to any one of claims 4 to 6, characterized in that: The welding strips (20) are multiple and arranged parallel to each other; There is one fixing member (30), and a plurality of rows of through holes are provided on the fixing member (30), the number of rows of through holes is the same as the number of the welding strips (20), and each row of through holes includes the laser holes (32) and the welding strip holes (31) that are alternately arranged; Alternatively, there are a plurality of fixing members (30), one fixing member (30) corresponds to one welding strip (20), each fixing member (30) is provided with a row of through holes, and each row of through holes includes the laser holes (32) and the welding strip holes (31) that are alternately arranged.

9. The back contact type battery sheet according to claim 1, characterized in that: The battery body (10) further comprises: A left grid line (13), the left grid line (13) being located on a side of the battery body (10), the left grid line (13) being used to connect one end of all the positive grid lines (11) and not being in contact with the negative grid line (12); a right grid line (14), the right grid line (14) being located at another side of the battery body (10), the right grid line (14) being used to connect one end of all the negative grid lines (12) and not being in contact with the positive grid line (11); Wherein, the left grid line (13) and the right grid line (14) are arranged in parallel, and the left grid line (13) and the positive grid line (11) are perpendicular to each other.

10. A photovoltaic module, characterized in that: The invention comprises a plurality of back-contact battery sheets according to any one of claims 1 to 9.

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