Preparation method of back contact cell string and photovoltaic module

Abstract

The invention relates to the technical field of photovoltaic cells, in particular to a preparation method of a back contact cell string and a photovoltaic module. The preparation method of the back contact cell string comprises the following steps: a glue setting step: setting insulation glue at a position, close to a first solder strip to be set, of a cell piece and on a second thin grid line, setting insulation glue at a position, close to a second solder strip to be set, of the cell piece and on the first thin grid line, and setting pre-solidified glue at the first solder strip to be set and the second solder strip to be set; the glue is cured, specifically, the glue is cured so that the insulation glue can be cured to the preset hardness, and the pre-cured glue is not cured or not completely cured; and a welding strip laying step: laying the first welding strip and the second welding strip. The photovoltaic module comprises the cell string formed by adopting the preparation method of the back contact cell string. The invention provides a preparation method of a back contact cell string and a photovoltaic module. The technical problem that in the prior art, the preparation process of a back contact cell is long is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photovoltaic cells, in particular to a preparation method of a back contact cell string and a photovoltaic module. BACKGROUND

[0002] BC (Back Contact) cell, also known as back contact cell, has PN junction and positive and negative electrodes all arranged on the back light surface of the cell sheet, and the light receiving surface of the cell sheet has no grid lines, which can maximize the light receiving area of the light receiving surface and reduce optical loss, thereby greatly improving the photoelectric conversion efficiency of the cell sheet.

[0003] Generally, the back contact cell sheet is provided with a first solder strip, a second solder strip, a plurality of first fine grid lines connected with the first solder strip, and a plurality of second fine grid lines connected with the second solder strip, and the polarities of the first fine grid lines and the second fine grid lines are opposite. In the prior art, the preparation method of the back contact cell is as follows: S1, printing insulating glue: printing insulating glue on the second fine grid lines near the position where the first solder strip is to be arranged on the back light surface of the cell sheet, and printing insulating glue on the first fine grid lines near the position where the second solder strip is to be arranged on the back light surface of the cell sheet, to prevent short circuit caused by contact between positive and negative electrodes; S2, curing the insulating glue: placing the cell sheet into a carding furnace to dry the insulating glue; S3, laying the solder strip: printing pre-fixing glue on the positions where the first solder strip and the second solder strip are to be arranged on the back light surface of the cell sheet, and laying the first solder strip and the second solder strip respectively, so that the first solder strip is connected to the cell sheet through the pre-fixing glue, and the second solder strip is connected to the cell sheet through the pre-fixing glue, and then curing the pre-fixing glue, to realize pre-fixing of the first solder strip and the second solder strip on the cell sheet.

[0004] However, in the above preparation process of the back contact cell, the insulating glue needs to be printed on the cell sheet first, and the pre-fixing glue needs to be printed after curing the insulating glue, that is, the cell sheet needs to be printed with glue twice, which makes the preparation process of the back contact cell long and the production efficiency low.

[0005] Therefore, the present application provides a new preparation method of a back contact cell string and a photovoltaic module to solve the above problems. SUMMARY

[0006] The first object of the present application is to provide a preparation method of a back contact cell string, to at least alleviate the technical problem of long preparation process of the back contact cell in the prior art.

[0007] The second object of the present application is to provide a photovoltaic module to further alleviate the technical problem of long preparation process of the back contact cell in the prior art.

[0008] Based on the above first purpose, the present application provides a preparation method of a back contact cell string, the back contact cell string comprising a cell sheet, the cell sheet being provided with a first solder strip, a second solder strip, a plurality of first fine grid lines each connected with the first solder strip, and a plurality of second fine grid lines each connected with the second solder strip, and the polarity of the first fine grid lines being opposite to that of the second fine grid lines, the preparation method of the back contact cell string comprising: a glue setting step of setting insulating glue on the second fine grid lines at a position of the cell sheet close to a position where the first solder strip is to be set, and setting insulating glue on the first fine grid lines at a position of the cell sheet close to a position where the second solder strip is to be set, and setting pre-solidified glue at the position where the first solder strip is to be set and at the position where the second solder strip is to be set; a glue solidifying step of solidifying the glue, so as to solidify the insulating glue to a preset hardness, and so as to make the pre-solidified glue not solidified or incompletely solidified; a solder strip laying step of laying the first solder strip at the position where the first solder strip is to be set, and laying the second solder strip at the position where the second solder strip is to be set, so as to make the first solder strip and the second solder strip cover the pre-solidified glue.

[0009] Further, in the glue setting step, the insulating glue and / or the pre-solidified glue is / are UV glue.

[0010] Further, in the glue solidifying step, the glue is solidified by ultraviolet irradiation, and the ultraviolet irradiated to the pre-solidified glue is shielded by a light mask device, so as to make the pre-solidified glue not solidified or incompletely solidified.

[0011] Further, the light mask device comprises a plurality of light mask plates, the plurality of light mask plates being capable of respectively shielding the ultraviolet irradiated directly to the pre-solidified glue and the ultraviolet irradiated to the pre-solidified glue by reflection.

[0012] Further, in the solder strip laying step, after the first solder strip and the second solder strip cover the pre-solidified glue, the pre-solidified glue is solidified, so that the first solder strip and the second solder strip are connected to the cell sheet through the pre-solidified glue.

[0013] Further, in the solder strip laying step, the solidification of the pre-solidified glue is incomplete.

[0014] Further, the cell sheet is a main grid cell sheet having a main grid line or a main grid-free cell sheet not having a main grid line; When the cell sheet is a main grid cell sheet, the main grid line comprises a first main grid line provided at the position where the first solder strip is to be set, and a second main grid line provided at the position where the second solder strip is to be set, and the plurality of first fine grid lines are each connected with the first main grid line, and the plurality of second fine grid lines are each connected with the second main grid line.

[0015] Further, the first solder strip and the second solder strip are arranged at the positions where the first solder strip and the second solder strip are to be arranged on the battery piece, and the PAD points are arranged at the positions where the first solder strip and the second solder strip are to be arranged on the battery piece.

[0016] Further, the width of the insulating glue is greater than the width of the first fine grid line, and / or the width of the insulating glue is greater than the width of the second fine grid line.

[0017] By adopting the technical scheme, the preparation method of the back contact battery string has at least the following beneficial effects: It should be noted that, in the glue setting step, the insulating glue is arranged to electrically isolate the first solder strip and the second fine grid line and to electrically isolate the second solder strip and the first fine grid line, so as to prevent short circuit caused by contact between the positive and negative electrodes on the battery piece; the pre-solidified glue is arranged to pre-fix the first solder strip at the position where the first solder strip is to be arranged on the battery piece and to pre-fix the second solder strip at the position where the second solder strip is to be arranged on the battery piece, so as to facilitate connection of the solder strips in subsequent processes. In the glue solidifying step, the insulating glue is solidified to a preset hardness, so that the insulating glue can form a stable insulating layer and effectively play an electrical isolation role; in the solder strip laying step, the first solder strip is laid at the position where the first solder strip is to be arranged, and the second solder strip is laid at the position where the second solder strip is to be arranged, so that the first solder strip and the second solder strip are both covered on the pre-solidified glue.

[0018] In the glue solidifying step, only the insulating glue is solidified to a preset hardness, and the pre-solidified glue is not solidified or is not completely solidified, so that the pre-solidified glue is in a sticky paste state with elasticity, so that in the solder strip laying step, the first solder strip and the second solder strip can be embedded in the pre-solidified glue, and the pre-solidified glue is then solidified, so that the first solder strip and the second solder strip can be pre-fixed on the battery piece.

[0019] That is, the preparation method of the back contact battery string according to the embodiment only needs to perform a printing operation of glue once in the glue setting step, compared with the two times of glue printing operations in the prior art, one printing operation of glue is reduced, so that the process of preparing the back contact battery is shortened, and the production efficiency of the back contact battery is improved.

[0020] Based on the second purpose, the application provides a photovoltaic module, which comprises a back contact battery string formed by the preparation method of the back contact battery string.

[0021] By adopting the technical scheme, the photovoltaic module has at least the following beneficial effects: The back contact cell string is formed by using the preparation method of the back contact cell string in a photovoltaic module, and the photovoltaic module has all the advantages of the preparation method of the back contact cell string, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced as follows. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0023] Figure 1 The structure schematic diagram of the cell piece after the glue is arranged on the main grid cell piece in the preparation method of the back contact cell string provided by the embodiments of the present application; Figure 2 The structure schematic diagram of the cell piece after the glue is arranged on the main grid cell piece in the preparation method of the back contact cell string provided by the embodiments of the present application; Figure 1 The structure enlarged view of part A in the above figure; Figure 3 The structure enlarged view of part B in the above figure; Figure 1 The structure enlarged view of part B in the above figure; Figure 4 The structure schematic diagram of the cell piece after the solder strip is laid on the main grid cell piece in the preparation method of the back contact cell string provided by the embodiments of the present application; Figure 1 The structure schematic diagram of the cell piece after the solder strip is laid on the main grid cell piece in the preparation method of the back contact cell string provided by the embodiments of the present application; Figure 5 The structure schematic diagram of the cell piece after the glue is arranged on the main grid cell piece in the preparation method of the back contact cell string provided by the embodiments of the present application; Figure 6 The structure enlarged view of part C in the above figure; Figure 5 The structure enlarged view of part C in the above figure; Figure 7 The structure enlarged view of part D in the above figure; Figure 5 The structure enlarged view of part D in the above figure; Figure 8 The structure schematic diagram of the cell piece after the solder strip is laid on the main grid cell piece in the preparation method of the back contact cell string provided by the embodiments of the present application; Figure 5 The structure schematic diagram of the cell piece after the solder strip is laid on the main grid cell piece in the preparation method of the back contact cell string provided by the embodiments of the present application; Figure 9 The flow chart of the preparation method of the back contact cell string provided by the embodiments of the present application.

[0024] Reference signs: 1-insulating glue; 2-pre-solidified glue; 31-first solder strip; 32-second solder strip; 41-first fine grid line; 42-second fine grid line; 5-PAD point; 61 - first main busbar; 62 - second main busbar. DETAILED DESCRIPTION

[0025] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0026] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0027] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0028] Embodiment one Please see Figure 9 , and in combination with Figure 1 With Figure 4 , the present embodiment provides a preparation method of a back contact battery string, the back contact battery string comprising a battery piece, the battery piece being provided with a first solder strip 31, a second solder strip 32, a plurality of first fine grid lines 41 each connected with the first solder strip 31, and a plurality of second fine grid lines 42 each connected with the second solder strip 32, and the polarities of the first fine grid lines 41 and the second fine grid lines 42 being opposite.

[0029] The preparation method of the back contact battery string comprises: The glue setting step: setting insulating glue 1 on the second fine grid line 42 at the position close to the first solder strip 31 to be set on the battery piece, setting insulating glue 1 on the first fine grid line 41 at the position close to the second solder strip 32 to be set on the battery piece, and setting pre-solidified glue 2 at the position of the first solder strip 31 to be set and the position of the second solder strip 32 to be set.

[0030] The curing glue step is to cure the glue to make the insulating glue 1 cured to a preset hardness and make the pre-curing glue 2 uncured or incompletely cured.

[0031] The laying solder strip step is to lay the first solder strip 31 at the position where the first solder strip 31 is to be arranged and lay the second solder strip 32 at the position where the second solder strip 32 is to be arranged, so that the first solder strip 31 and the second solder strip 32 are both covered on the pre-curing glue 2.

[0032] It should be noted that, in the arranging glue step, the insulating glue 1 is arranged to electrically isolate the first solder strip 31 from the second fine grid line 42 and electrically isolate the second solder strip 32 from the first fine grid line 41, so as to prevent the short circuit caused by the contact between the positive and negative electrodes on the battery piece; the pre-curing glue 2 is arranged to pre-fix the first solder strip 31 at the position where the first solder strip 31 is to be arranged on the battery piece and pre-fix the second solder strip 32 at the position where the second solder strip 32 is to be arranged on the battery piece, so as to facilitate the connection of the solder strips in the subsequent process. In the curing glue step, the insulating glue 1 is cured to a preset hardness, so that the insulating glue 1 can form a stable insulating layer and can effectively play an electrical isolation role; in the laying solder strip step, the first solder strip 31 is laid at the position where the first solder strip 31 is to be arranged and the second solder strip 32 is laid at the position where the second solder strip 32 is to be arranged, so that the first solder strip 31 and the second solder strip 32 are both covered on the pre-curing glue 2.

[0033] In the curing glue step, only the insulating glue 1 is cured to a preset hardness, while the pre-curing glue 2 is not cured or incompletely cured, at this time the pre-curing glue 2 is in a sticky state with elasticity, so that in the laying solder strip step, the first solder strip 31 and the second solder strip 32 can be embedded in the pre-curing glue 2, and then the pre-curing glue 2 is cured to pre-fix the first solder strip 31 and the second solder strip 32 on the battery piece.

[0034] That is, the preparation method of the back contact battery string of the embodiment only needs to perform one printing operation of the glue in the arranging glue step, compared with the two times of glue printing operations in the prior art, one printing process of the glue is reduced, so that the process of preparing the back contact battery is shortened and the production efficiency of the back contact battery is improved.

[0035] Optionally, the insulating glue 1 and / or the pre-curing glue 2 is arranged on the battery piece by screen printing, coating or 3D printing.

[0036] Preferably, please refer to Figure 9In the embodiment, the preparation method of the back contact cell string further includes a solder ribbon connecting step after the solder ribbon laying step. The solder ribbon connecting step includes: welding the first solder ribbon 31 and the second solder ribbon 32 to the cell, so that the first solder ribbon 31 and the second solder ribbon 32 are both electrically connected to the cell. The cell can be placed in a laminator for lamination and curing, so as to realize the welding of the first solder ribbon 31 and the second solder ribbon 32 to the cell.

[0037] Optionally, the insulating glue 1 is UV glue, or the pre-solidifying glue 2 is UV glue, or both the insulating glue 1 and the pre-solidifying glue 2 are UV glue. Preferably, in the embodiment, both the insulating glue 1 and the pre-solidifying glue 2 are UV glue.

[0038] The UV glue is also called shadowless glue, photosensitive glue or ultraviolet light curing glue, which is a single-component adhesive that needs to be cured by ultraviolet irradiation.

[0039] In this way, both the insulating glue 1 and the pre-solidifying glue 2 are UV glue, so that the insulating glue 1 and the pre-solidifying glue 2 can be cured within a few seconds under ultraviolet irradiation. Compared with traditional heat-curing adhesives, the curing time is greatly shortened, the production efficiency is significantly improved, the equipment and space costs are reduced, and the demand for large-scale production is met. In addition, the UV glue only needs to be cured under ultraviolet irradiation, which is a low-temperature curing method, which can greatly reduce the degree of cell warping and help improve the performance and quality of the cell.

[0040] Preferably, in the embodiment, in the curing glue step, the glue is cured by ultraviolet irradiation, and the ultraviolet light irradiated on the pre-solidifying glue 2 is shielded by a light shielding device, so that the pre-solidifying glue 2 is not cured or not completely cured.

[0041] In this way, the insulating glue 1 is cured to a preset hardness by ultraviolet irradiation, and the ultraviolet light irradiated on the pre-solidifying glue 2 is shielded by a light shielding device, so that the pre-solidifying glue 2 is not cured or not completely cured, so that the pre-solidifying glue 2 can be cured and connected to the subsequently laid solder ribbon.

[0042] Preferably, in the embodiment, the light shielding device includes a plurality of light shielding plates, which can shield the ultraviolet light directly irradiated on the pre-solidifying glue 2 and the ultraviolet light reflected to the pre-solidifying glue 2.

[0043] In this way, the ultraviolet light is prevented from irradiating on the pre-solidifying glue 2, so that the pre-solidifying glue 2 is cured and cannot be cured and connected to the subsequently laid first solder ribbon 31 and second solder ribbon 32.

[0044] Preferably, in the embodiment, in the solder ribbon laying step, the first solder ribbon 31 and the second solder ribbon 32 are both covered on the pre-solidifying glue 2, and then the pre-solidifying glue 2 is cured, so that the first solder ribbon 31 and the second solder ribbon 32 are connected to the cell through the pre-solidifying glue 2.

[0045] Pre-curing of the pre-curing adhesive 2 is preferably incomplete during the step of laying the solder ribbons. For example, the pre-curing adhesive 2 can be 10% cured, 20% cured, 30% cured, 40% cured, or 50% cured, etc.

[0046] With the pre-curing adhesive 2 being incompletely cured, on the one hand, the pre-curing adhesive 2 has a certain degree of hardness, which can pre-fix the first solder ribbon 31 and the second solder ribbon 32 to the battery piece, facilitating subsequent welding of the first solder ribbon 31 and the second solder ribbon 32. On the other hand, since the pre-curing adhesive 2 is in an incompletely cured state with elasticity and stickiness, after the first solder ribbon 31 and the second solder ribbon 32 are embedded in the pre-curing adhesive 2, the pre-curing adhesive 2 can play a certain buffering role between the first solder ribbon 31 and the battery piece and between the second solder ribbon 32 and the battery piece, so as to keep the first solder ribbon 31 and the second solder ribbon 32 flexible and buffered, thereby preventing the battery piece from being directly pressed by the first solder ribbon 31 and the second solder ribbon 32 during the subsequent welding step, and preventing the battery piece from being cracked to some extent, thereby improving the reliability of the battery piece.

[0047] Optionally, the battery piece of the present embodiment can be a main-grid battery piece with main-grid lines, or a main-grid-free battery piece without main-grid lines. Please refer to Figure 1 , Figure 2 and Figure 3 . When the battery piece is a main-grid battery piece, the main-grid lines include a first main-grid line 61 arranged at the position where the first solder ribbon 31 is to be arranged, and a second main-grid line 62 arranged at the position where the second solder ribbon 32 is to be arranged, and each of the plurality of first fine-grid lines 41 is connected to the first main-grid line 61, and each of the plurality of second fine-grid lines 42 is connected to the second main-grid line 62.

[0048] Please refer to Figure 1 , Figure 2 and Figure 3 . When the battery piece is a main-grid battery piece, i.e., the battery piece has main-grid lines, at this time, the plurality of first fine-grid lines 41 are used to collect the current of the first polarity on the battery piece and converge to the first main-grid line, and the current is conducted to the first solder ribbon 31 through the first main-grid line 61, and the plurality of second fine-grid lines 42 are used to collect the current of the second polarity on the battery piece and converge to the second main-grid line, and the current is conducted to the second solder ribbon 32 through the second main-grid line 62, and the first polarity and the second polarity are opposite.

[0049] Please refer to Figure 5 , Figure 6 , Figure 7 and Figure 8, the battery piece is a back contact battery piece, and the battery piece is a back contact battery piece applying 0BB technology. The 0BB (Zero Busbar) technology is an innovative process of canceling the busbar in the traditional battery piece. The use amount of silver paste is reduced by connecting the busbar with the fine busbar on the battery piece directly, and the process cost is reduced. At this time, the plurality of first fine busbars 41 are used to collect the current of the first polarity on the battery piece and are collected to the first busbar 31, and the plurality of second fine busbars 42 are used to collect the current of the second polarity on the battery piece and are collected to the second busbar 32.

[0050] Preferably, referring to Figure 2 and Figure 6 In the embodiment, the PAD point 5 is arranged at the position where the first busbar 31 is arranged and the position where the second busbar 32 is arranged on the battery piece. The pre-glue 2 is arranged at intervals with the PAD point 5, or the pre-glue 2 is arranged by covering part of the PAD point 5.

[0051] It should be noted that the PAD point 5 can be thickened to form the first fine busbar 41 and / or the second fine busbar 42, or the PAD point 5 can be formed by printing the conductive metal on the battery piece.

[0052] Optionally, the width of the insulating glue 1 is greater than the width of the first fine busbar 41, or the width of the insulating glue 1 is greater than the width of the second fine busbar 42.

[0053] Preferably, in the embodiment, the width of the insulating glue 1 is greater than the width of the first fine busbar 41, and the width of the insulating glue 1 is greater than the width of the second fine busbar 42, so as to ensure the electrical isolation effect of the busbar and the fine busbar.

[0054] Embodiment two Embodiment two provides a photovoltaic module, in which the back contact battery string is formed by the preparation method of the back contact battery string disclosed in embodiment one. The technical features of the preparation method of the back contact battery string disclosed in embodiment one are also applicable to this embodiment. The photovoltaic module described in this embodiment has the advantages of the preparation method of the back contact battery string described in embodiment one, which has been described in detail in embodiment one and will not be repeated here.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing a back-contact battery string, the back-contact battery string comprising a battery cell, wherein the battery cell is provided with a first solder strip (31), a second solder strip (32), a plurality of first fine grid lines (41) all connected to the first solder strip (31), and a plurality of second fine grid lines (42) all connected to the second solder strip (32), and the polarities of the first fine grid lines (41) and the second fine grid lines (42) are opposite, characterized in that, The method for preparing the back contact battery string includes: Steps for setting adhesive: When the battery cell is close to the first welding strip (31) to be set, insulating adhesive (1) is set on the second fine grid line (42); when the battery cell is close to the second welding strip (32) to be set, insulating adhesive (1) is set on the first fine grid line (41); and pre-curing adhesive (2) is set at both the first welding strip (31) to be set and the second welding strip (32) to be set. Curing adhesive step: Curing the adhesive to cure the insulating adhesive (1) to a preset hardness, and to leave the pre-cured adhesive (2) uncured or incompletely cured; Steps for laying welding strips: Lay the first welding strip (31) at the location where the first welding strip (31) is to be laid, and lay the second welding strip (32) at the location where the second welding strip (32) is to be laid, so that both the first welding strip (31) and the second welding strip (32) are covered by the pre-curing adhesive (2).

2. The method for preparing a back contact battery string according to claim 1, characterized in that, In the adhesive application step, the insulating adhesive (1) and / or the pre-curing adhesive (2) are UV adhesives.

3. The method for preparing a back contact battery string according to claim 2, characterized in that, In the curing adhesive step, the adhesive is cured by irradiating it with ultraviolet light, and the ultraviolet light irradiating the pre-cured adhesive (2) is blocked by a photomask so that the pre-cured adhesive (2) is not cured or is not fully cured.

4. The method for preparing a back contact battery string according to claim 3, characterized in that, The photomask device includes multiple photomasks, which can respectively block ultraviolet rays that directly irradiate the precuring adhesive (2) and ultraviolet rays that are reflected to the precuring adhesive (2).

5. The method for preparing a back contact battery string according to claim 1, characterized in that, In the step of laying the welding strip, after the first welding strip (31) and the second welding strip (32) are covered by the pre-curing adhesive (2), the pre-curing adhesive (2) is cured, so that the first welding strip (31) and the second welding strip (32) are connected to the battery cell through the pre-curing adhesive (2).

6. The method for preparing a back contact battery string according to claim 5, characterized in that, In the step of laying the welding strip, the pre-cured adhesive (2) is cured incompletely.

7. The method for preparing a back contact battery string according to any one of claims 1-6, characterized in that, The solar cell is either a solar cell with main grid lines or a solar cell without main grid lines; When the battery cell is a battery cell with a main grid, the main grid line includes a first main grid line (61) disposed at the first solder strip (31) to be disposed and a second main grid line (62) disposed at the second solder strip (32) to be disposed, and multiple first fine grid lines (41) are connected to the first main grid line (61), and multiple second fine grid lines (42) are connected to the second main grid line (62).

8. The method for preparing a back contact battery string according to any one of claims 1-6, characterized in that, On the battery cell, PAD points (5) are also provided at the first solder strip (31) to be set and the second solder strip (32) to be set. The pre-curing adhesive (2) is provided at intervals with the PAD points (5), or the pre-curing adhesive (2) is provided to cover part of the PAD points (5).

9. The method for preparing a back contact battery string according to any one of claims 1-6, characterized in that, The width of the insulating adhesive (1) is greater than the width of the first fine grid line (41), and / or the width of the insulating adhesive (1) is greater than the width of the second fine grid line (42).

10. A photovoltaic module, characterized in that, It includes a back contact battery string, which is formed by the method for preparing a back contact battery string according to any one of claims 1-9.

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