Photovoltaic module, electric connection structure and preparation method of photovoltaic module

Abstract

The invention discloses a photovoltaic module, an electric connection structure and a preparation method of the photovoltaic module. The photovoltaic module comprises a plurality of battery strings, wherein each battery string comprises a plurality of battery pieces and a plurality of electric connection units; each electric connection unit is used for connecting fine grid lines of two adjacent battery pieces in series; the electric connection unit comprises a plurality of first conductive bands which are arranged side by side at intervals and a second conductive band which is connected with the plurality of first conductive bands in series, and the plurality of first conductive bands are in one-to-one correspondence with the fine grid lines on one main surface of the battery piece; the extension direction of each first conductive band is consistent with the extension direction of the fine grid lines, and each first conductive band covers and is connected in series with two corresponding fine grid lines on two adjacent battery pieces; the second conductive bands are arranged at the ends of the first conductive bands in the extending direction, and the second conductive bands and the first conductive bands are of an integrated structure so that the distances between the first conductive bands can be fixed. According to the photovoltaic module, the current transmission loss can be reduced, so that the performance of the photovoltaic module is effectively improved.

Description

Technical Field

[0001] The invention relates to a photovoltaic component, an electrical connection structure and a method for preparing the photovoltaic component. Background Art

[0002] At present, two adjacent cells in a photovoltaic module are generally connected in series through multiple welding strips, each welding strip is connected to a main grid line perpendicular to the fine grid line, or the welding strip is directly connected to multiple fine grid lines perpendicularly. This existing structure requires alignment of the welding strips, and during the transmission of the fine grid lines, the current needs to travel a certain transmission distance on the fine grid lines before reaching the welding strips, which inevitably causes current transmission loss, affecting the performance of the photovoltaic module. Summary of the invention

[0003] In view of this, the present invention provides a photovoltaic module, an electrical connection structure and a method for preparing a photovoltaic module, wherein the photovoltaic module can reduce current transmission loss to effectively improve the performance of the photovoltaic module. In addition, the second conductive tape in the electrical connection unit of the photovoltaic module is an integrated structure with the plurality of first conductive tapes, and the second conductive tape fixes the spacing between the plurality of first conductive tapes, facilitating the positioning between the electrical connection unit and the cell, making the photovoltaic module structure simple, and the preparation process of the photovoltaic module is also simplified.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] In a first aspect, the present invention provides a photovoltaic module, comprising: a plurality of battery strings, wherein:

[0006] The battery string comprises: a plurality of battery cells and a plurality of electrical connection units;

[0007] Each of the electrical connection units is used to connect in series the fine grid lines of two adjacent battery cells;

[0008] The electrical connection unit includes: a plurality of first conductive strips arranged side by side and at intervals and a second conductive strip connected in series with the plurality of first conductive strips, wherein:

[0009] The plurality of first conductive strips correspond one-to-one to the fine grid lines on one main surface of the battery cell;

[0010] The extension direction of each of the first conductive strips is consistent with the extension direction of the thin grid lines, and each of the first conductive strips covers and connects in series two corresponding thin grid lines on two adjacent battery cells;

[0011] The second conductive strip is disposed at the end of the plurality of first conductive strips in the extending direction and is an integral structure with the plurality of first conductive strips to fix the intervals between the plurality of first conductive strips.

[0012] In a second aspect, an embodiment of the present invention provides an electrical connection structure, which is applied to a photovoltaic module and includes: a plurality of electrical connection units, wherein:

[0013] The plurality of electrical connection units are arranged along a first direction and are an integrated structure;

[0014] Each of the electrical connection units is used to connect two adjacent cells in the photovoltaic module in series;

[0015] The electrical connection unit includes: a plurality of first conductive strips arranged side by side and at intervals and a second conductive strip connected in series with the plurality of first conductive strips, wherein:

[0016] The plurality of first conductive strips correspond one-to-one to the fine grid lines on the cell sheet of the photovoltaic module;

[0017] The extending direction of each of the first conductive strips is consistent with the extending direction of the fine gate lines, wherein the extending direction of the first conductive strips is consistent with the first direction;

[0018] The two second conductive strips are respectively arranged at two ends of the plurality of first conductive strips and are an integral structure with the plurality of first conductive strips to fix the intervals between the plurality of first conductive strips.

[0019] In a third aspect, an embodiment of the present invention provides a method for preparing a photovoltaic module provided by the embodiment of the first aspect, comprising:

[0020] Step 1, alternately laying electrical connection units and battery cells to obtain a battery string, wherein every two adjacent battery cells are connected to one electrical connection unit, wherein each fine grid line on the battery cell is placed corresponding to a first conductive strip of the electrical connection unit;

[0021] Step 2: assemble the battery string.

[0022] The technical solution of the first aspect of the above invention has the following advantages or beneficial effects:

[0023] The photovoltaic module provided by the embodiment of the present invention directly contacts the fine grid line through the first conductive belt, extracts the current of the fine grid line, and balances the current of each first conductive belt through the second conductive belt, omitting the main grid line and the welding belt formed with the main grid line, providing a photovoltaic module with a new structure, and at the same time can reduce the current transmission path, reduce current loss, and effectively improve the performance of the photovoltaic module. In addition, the current transmitted by each first conductive belt is balanced by the second conductive belt, ensuring that the current transmitted by each battery cell in the photovoltaic module is balanced and stable, so as to further improve the performance of the photovoltaic module.

[0024] In addition, since the second conductive tape and the multiple first conductive tapes are an integral structure and the second conductive tape fixes the spacing between the multiple first conductive tapes, the multiple first conductive tapes can be aligned with their corresponding fine grid lines at the same time through one positioning, without the need to align each first conductive tape individually, thereby simplifying the photovoltaic module manufacturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a partial structural schematic diagram of a first structure of a battery string in a photovoltaic assembly according to an embodiment of the present invention;

[0026] Figure 2 is a partial structural schematic diagram of a second structure of a battery string in a photovoltaic assembly according to an embodiment of the present invention;

[0027] Figure 3 According to an embodiment of the present invention, the Figure 2 A partial structural schematic diagram of an electrical connection unit in a battery string shown;

[0028] Figure 4 is a schematic diagram of a partial cross-sectional structure of a photovoltaic module parallel to the fine grid lines according to an embodiment of the present invention;

[0029] Figure 5 (A) is a schematic diagram of a side view of an electrical connection structure according to an embodiment of the present invention, and (B) is a schematic diagram of a planar structure of an unfolded electrical connection structure according to an embodiment of the present invention;

[0030] Figure 6 is a structural schematic diagram of an electrical connection unit in an electrical connection structure according to an embodiment of the present invention;

[0031] Figure 7 is another structural schematic diagram of an electrical connection unit in an electrical connection structure according to an embodiment of the present invention;

[0032] Figure 8 is a method according to an embodiment of the present invention corresponding to Figure 7 A schematic diagram of a deformed structure of an electrical connection unit;

[0033] Fig. 9 is a schematic diagram of a first cross-sectional structure of a first conductive tape according to an embodiment of the present invention;

[0034] Fig.10 is a schematic diagram of a second cross-sectional structure of a first conductive tape according to an embodiment of the present invention;

[0035] Fig.11 is a partial schematic diagram of structural changes in a process of laying a battery string in a photovoltaic module according to an embodiment of the present invention;

[0036] Fig.12is a partial structural schematic diagram of a structure for fixing cells in a cell string in a photovoltaic module according to an embodiment of the present invention;

[0037] Fig.13 is a partial structural schematic diagram of another structure for fixing cells in a cell string in a photovoltaic module according to an embodiment of the present invention;

[0038] Fig.14 It is a schematic diagram of the main process of the photovoltaic module preparation method according to an embodiment of the present invention.

[0039] The reference numerals are as follows:

[0040] 10-battery string; 11-battery cell; 111-fine grid line; 12-electrical connection unit; 121-first conductive strip; 122-second conductive strip; 123-third conductive strip; 124-welding layer; 125-cutting part; 126-cutting position; 20-cover plate; 30-packaging layer; 40-back plate; 50-bonding point; 60-fixing film; 70-electrical connection structure. DETAILED DESCRIPTION

[0041] The photovoltaic module involved in the embodiment of the present invention can be any type of photovoltaic module, such as a double-glass module, a single-glass module, etc. Among them, the cell used in the photovoltaic module can be cut from any solar cell without a main grid line (such as a silicon-based solar cell, a perovskite solar cell, etc., wherein the silicon-based solar cell can be a cross-finger type, a back contact type, a type with electrodes set on both sides, etc.).

[0042] The embodiment of the present invention improves the structure of the photovoltaic module, omits the main grid line, and directly connects the battery cell in series with the second conductive strip 122 and the plurality of first conductive strips 121 of the integral structure and the fine grid line 111, wherein the first conductive strip 121 corresponds to the fine grid line 111 one by one, and no welding strip is required. On the one hand, the spacing between each adjacent two first conductive strips 121 in the plurality of first conductive strips 121 is limited by the second conductive strip 122, that is, the existence of the second conductive strip 122 can realize synchronous positioning of the plurality of first conductive strips 121 through a single positioning operation, thereby simplifying the process operation of the photovoltaic module; on the other hand, by omitting the main grid line and the welding strip, the production cost of the photovoltaic module can be effectively reduced. In addition, the second conductive strip 122 is an integral structure with the plurality of first conductive strips 121, and the second conductive strip 122 is arranged at the end of the extension direction of the plurality of first conductive strips 121, so that the second conductive strip 122 can balance the current and power of the battery cell, and the photovoltaic module omits the main grid line and the welding strip, thereby reducing the shading area of ​​the photovoltaic module, thereby effectively improving the performance of the photovoltaic module.

[0043] in, Figure 1This is a schematic diagram of a first structure of a battery string in a photovoltaic assembly provided by an embodiment of the present invention; Figure 2 This is a second structural schematic diagram of a battery string in a photovoltaic assembly provided by an embodiment of the present invention; Figure 3 According to an embodiment of the present invention, the Figure 2 A schematic structural diagram of an electrical connection unit in a battery string shown; Figure 4 It is a schematic diagram of the cross-sectional structure of a photovoltaic module provided by an embodiment of the present invention parallel to the fine grid lines.

[0044] An embodiment of the present invention provides a photovoltaic module. Figure 4 As shown, the photovoltaic assembly may include: a plurality of battery strings 10, wherein:

[0045] like Figure 1 , Figure 2 and Figure 4 As shown, the battery string 10 may include: a plurality of battery cells 11 and a plurality of electrical connection units 12;

[0046] Each electrical connection unit 12 is used to connect in series the fine grid lines 111 of two adjacent battery cells 11;

[0047] The electrical connection unit 12 may include: a plurality of first conductive strips 121 arranged side by side and at intervals, and a second conductive strip 122 connecting the plurality of first conductive strips 121 in series, wherein:

[0048] The plurality of first conductive strips 121 correspond one to one with the fine grid lines 111 on one main surface of the battery cell 11;

[0049] The extension direction of each first conductive strip 121 is consistent with the extension direction of the thin grid lines 111, and each first conductive strip 121 covers and connects in series two corresponding thin grid lines on two adjacent battery cells 11;

[0050] The second conductive strips 122 are disposed at the ends of the first conductive strips 121 in the extending direction and are integrated with the first conductive strips 121 to fix the intervals between the first conductive strips 121 .

[0051] The plurality of first conductive strips 121 and second conductive strips 122 of the integrated structure are formed by punching a conductive plate through a stamping process.

[0052] Understandably, if Figure 4 As shown, in addition to the above-mentioned battery string 10, the photovoltaic module provided by the embodiment of the present invention may also include a cover plate 20, an encapsulation layer 30 and a back plate 40, wherein the encapsulation layer 30 is used to encapsulate the battery string between the cover plate 20 and the back plate 40. A plurality of battery strings 10 may be included in the photovoltaic module, and the plurality of battery strings are connected in series and parallel to form a battery array. Figure 4Based on the partial structure of the photovoltaic module and the partial structure of the battery string provided by the embodiment of the present invention, those skilled in the art can know the complete structure of the photovoltaic module provided by the embodiment of the present invention.

[0053] The photovoltaic module provided in the embodiment of the present invention generally includes a cell 11 whose electrodes have no main grid lines but only fine grid lines 111 .

[0054] Among them, in the above-mentioned integrated electrical connection unit 12, multiple first conductive strips 121 cross the second conductive strips 122, and preferably, multiple first conductive strips 121 are perpendicular to the second conductive strips 122. Specifically, the extension direction of multiple first conductive strips 121 is perpendicular to the extension direction of the second conductive strips 122. Based on this, the second conductive strips 122 are electrically connected to the same type of fine grid lines 111 on the battery cell to balance the current transmitted by each fine grid line 111 and ensure the current transmission capacity of the battery cell.

[0055] Each first conductive strip 121 is connected to two opposite thin grid lines 111 on two adjacent battery cells 11 by welding or bonding.

[0056] Among them, the two corresponding fine grid lines on two adjacent battery cells 11 generally refer to two fine grid lines with opposite electrical properties and close distances on two adjacent battery cells. For example, for a structure in which both the N-type structure and the P-type structure are arranged on the back of the battery cell 11, the fine grid line 111 on the N-type structure on one battery cell 11 is the fine grid line 111 on the P-type structure on another adjacent battery cell that is closest to it. For the N-type structure and the P-type structure that are arranged on the two main surfaces of the battery cell 11, specifically, the fine grid line 111 on the first main surface (such as the main surface with the N-type structure) of one battery cell 11 is the fine grid line 111 on the second main surface (such as the main surface with the P-type structure) of another adjacent battery cell 11 that is closest to the fine grid line 111 on the first main surface (such as the main surface with the N-type structure).

[0057] The number of the second conductive strips 122 can be one or two. Specifically, when the number of the second conductive strips 122 is one, the second conductive strips 122 are disposed on one side of a battery cell 11. Figure 1 As shown, in the case where there are two second conductive strips 122 , the two second conductive strips 122 are disposed on two sides of two adjacent battery cells 11 that are farthest apart.

[0058] The spacing between each two adjacent first conductive strips 121 is equal to the spacing between two fine grid lines 111 of the same type on one main surface of the battery cell 11. For example, for a structure with fine grid lines 111 of the same type on one main surface of the battery cell 11, the spacing between two fine grid lines 111 of the same type is the spacing between two adjacent fine grid lines 111. For an N-type structure and a P-type structure arranged alternately on one main surface of the battery cell 11, the spacing between two fine grid lines 111 of the same type is the spacing between the fine grid lines 111 on two adjacent N-type structures and the spacing between the fine grid lines 111 on two adjacent P-type structures.

[0059] Furthermore, if Fig. 9 and Fig.10 As shown, the cross section of the first conductive strip 121 may be circular, semicircular, inverted triangular, inverted trapezoidal or rectangular. Fig.10 As shown, the same first conductive tape 121 can be divided into two parts, and the cross sections of the two parts correspond to different structures, so as to meet the needs of users for different first conductive tapes 121 .

[0060] In addition, the cross section of the second conductive strip 122 may also be circular, semicircular, inverted triangular, inverted trapezoidal, or rectangular.

[0061] Furthermore, the thickness of the first conductive tape 121 may be 50 μm to 300 μm. For example, the thickness of the first conductive tape 121 may be 50 μm, 70 μm, 80 μm, 90 μm, 100 μm, 120 μm, 140 μm, 150 μm, 170 μm, 180 μm, 200 μm, 220 μm, 240 μm, 250 μm, 270 μm, 290 μm or 300 μm. By limiting the thickness of the first conductive tape 121, the conductivity of the first conductive tape 121 can be guaranteed, and the first conductive tape 121 can form a stable connection structure with the fine grid line 111. It is worth noting that the thickness of the first conductive tape 121 refers to the length of the first conductive tape 121 in the thickness direction of the photovoltaic module. For example, if the cross-section of the first conductive tape 121 is a circle, the thickness of the first conductive tape 121 is the diameter of the circle; if the cross-section of the first conductive tape 121 is a semicircle, the thickness of the first conductive tape 121 is the radius of the circle; if the cross-section of the first conductive tape 121 is an inverted triangle or an inverted trapezoid, the thickness of the first conductive tape 121 is the height of the triangle or the inverted trapezoid.

[0062] Further, the thickness of the second conductive tape 122 may be 50 μm to 300 μm. For example, the thickness of the second conductive tape 122 may be 50 μm, 60 μm, 70 μm, 90 μm, 100 μm, 120 μm, 135 μm, 140 μm, 150 μm, 170 μm, 180 μm, 200 μm, 220 μm, 240 μm, 250 μm, 270 μm, 290 μm or 300 μm, etc. By limiting the thickness of the second conductive tape 122, the conductivity of the second conductive tape 122 can be guaranteed, and the second conductive tape 122 can be guaranteed to have a relatively strong pulling force, so as to stably limit the first conductive tape 121. Among them, the thickness of the second conductive tape 122 may be the same as the thickness of the first conductive tape 121, and the thickness of the second conductive tape 122 may also be greater than the thickness of the first conductive tape 121. It is worth noting that the thickness of the second conductive tape 122 refers to the length of the second conductive tape 122 in the thickness direction of the photovoltaic module. For example, if the cross section of the second conductive tape 122 is a circle, the thickness of the second conductive tape 122 is the diameter of the circle; if the cross section of the second conductive tape 122 is a semicircle, the thickness of the second conductive tape 122 is the radius of the circle; if the cross section of the second conductive tape 122 is an inverted triangle or an inverted trapezoid, the thickness of the second conductive tape 122 is the height of the triangle or the inverted trapezoid.

[0063] The first conductive strips 121 and the second conductive strips 122 can be formed of copper-based materials such as phosphor bronze, beryllium bronze or oxygen-free copper. More specifically, the first conductive strips 121 and the second conductive strips 122 of the integrated structure are formed by stamping a conductive plate through a stamping process, so that the first conductive strips 121 and the second conductive strips 122 form a complete integrated structure.

[0064] For the photovoltaic module provided by the embodiment of the present invention, the first conductive tape 121 directly contacts the fine grid line 111 to extract the current of the fine grid line 111, and the second conductive tape 122 is used to balance the current of each first conductive tape 121, omitting the main grid line and the welding tape formed with the main grid line, providing a photovoltaic module with a new structure, while being able to reduce the current transmission path, reduce current loss, and effectively improve the performance of the photovoltaic module. In addition, the second conductive tape 122 is used to balance the current transmitted by each first conductive tape 121, ensuring that the current transmitted by each battery cell 11 in the photovoltaic module is balanced and stable, so as to further improve the performance of the photovoltaic module.

[0065] In addition, since the second conductive tape 122 and the multiple first conductive tapes 121 are an integral structure and the second conductive tape 122 fixes the spacing between the multiple first conductive tapes 121, the multiple first conductive tapes 121 and their corresponding fine grid lines 111 can be aligned simultaneously through one positioning, without the need to align each first conductive tape 121 individually, thereby simplifying the photovoltaic module manufacturing process.

[0066] Furthermore, if Figure 2 and Figure 3 As shown, the electrical connection unit 12 further includes: at least one third conductive strip 123, wherein the third conductive strip 123 is disposed between the two second conductive strips 122, and the third conductive strip 123 intersects with the plurality of first conductive strips 121 and forms an integral structure with the plurality of first conductive strips 121. Figure 2 and Figure 3 As shown, the extension direction of the third conductive tape 123 is perpendicular to the extension direction of the first conductive tape 121. The third conductive tape 123 intersects with the plurality of first conductive tapes 121, so that the third conductive tape 123 cooperates with the second conductive tape 122, thereby improving the limiting and fixing capabilities of the plurality of first conductive tapes 121, so as to more conveniently operate the synchronization of the plurality of first conductive tapes 121 with the corresponding fine grid lines 111, and improve the operability of the photovoltaic module production process. Furthermore, the third conductive tape 123 is electrically connected to the fine grid lines 111 of the same type on the cell, so as to further ensure the uniform distribution of current transmission on each fine grid line 111 on the cell, which helps to further improve the performance of the photovoltaic module.

[0067] More specifically, if Figure 2 and Figure 3 As shown, for the structure in which the electrical connection unit 12 includes at least one third conductive tape 123, a structure that can be realized is: at least one third conductive tape 123 is parallel to the second conductive tape 122; preferably, for the case in which there are multiple third conductive tapes 123, the multiple third conductive tapes 123 are distributed at equal intervals in the extension direction of the first conductive tape 121. By having at least one third conductive tape 123 parallel to the second conductive tape 122, the electrical connection unit 12 is easily prepared.

[0068] Furthermore, if Figure 4 As shown, the electrical connection unit 12 may further include a welding layer 124, wherein the welding layer 124 is wrapped around the first conductive strip 121 and the second conductive strip 122. The welding layer increases the welding tension between the first conductive strip 121 and the second conductive strip 122 and the fine grid line 111.

[0069] More specifically, the thickness of the welding layer 124 may be 5 μm to 25 μm. For example, the thickness of the welding layer 124 is 5 μm, 8 μm, 10 μm, 12 μm, 15 μm, 18 μm, 20 μm, 22 μm, 23 μm or 25 μm. The thickness of the welding layer 124 can be used to ensure the welding tension between the first conductive strip 121 and the second conductive strip 122 and the fine grid line 111, and to reduce the consumption of the welding layer 124 material as much as possible. The welding layer may be any one of tin, tin-lead, tin-lead-bismuth, tin-bismuth-silver, tin-silver-copper, and the like.

[0070] There can be two preparation processes for the welding layer 124. Specifically, the first preparation process for the welding layer 124 is: unfold the electrical connection unit 12, and sequentially undergo degreasing treatment, water washing treatment, pickling treatment, water washing treatment, electroplating treatment, water washing treatment and drying treatment. The second preparation process for the welding layer 124 is: unfold the electrical connection unit 12, and sequentially undergo annealing treatment, surface pre-coating flux treatment and hot dip plating treatment. Among them, the parameters used in each treatment process can be determined based on experimental data.

[0071] Furthermore, if Fig.12 As shown, the photovoltaic module may further include: bonding points 50 arranged at intervals on the fine grid lines 11 , and the first conductive tape 121 may be further stabilized by the bonding points 50 .

[0072] Furthermore, if Fig.13 As shown, the photovoltaic assembly may further include: a fixing film 60 covering the electrical connection unit 12 , and the first conductive tape 121 may be further stabilized by the fixing film 60 .

[0073] Furthermore, an embodiment of the present invention provides an electrical connection structure, which is applied to a photovoltaic module. Specifically, Figure 5 (A) and Figure 5 As shown in (B), the electrical connection structure may include: a plurality of electrical connection units 12, wherein the plurality of electrical connection units 12 are arranged along a first direction and the plurality of electrical connection units 12 are an integrated structure. Figure 5 As shown in (A), the electrical connection structure is generally placed in a crimped manner.

[0074] like Figure 1 and Figure 2 As shown, each electrical connection unit 12 is used to connect two adjacent cells 11 in the photovoltaic module in series;

[0075] More specifically, if Figure 1 , Figure 2 Figure 3 , Figure 5 (B) and Figures 6 to 8 As shown, the electrical connection unit 12 may include: a plurality of first conductive tapes 121 arranged side by side and at intervals, and a second conductive tape 122 connected in series with the plurality of first conductive tapes 121, the plurality of first conductive tapes 121 corresponding one-to-one to the fine grid lines 111 on the cell sheet 11 of the photovoltaic module; the extension direction of each first conductive tape 121 is consistent with the extension direction of the fine grid lines 111, wherein the extension direction of the first conductive tape 121 is consistent with the first direction; two second conductive tapes 122 are arranged at both ends of the plurality of first conductive tapes 121, and are an integral structure with the plurality of first conductive tapes 121 to fix the spacing between the plurality of first conductive tapes 121.

[0076] The plurality of first conductive strips 121 correspond one-to-one to the fine grid lines 111 on one main surface of the battery cell 11 .

[0077] The electrical connection unit 12 in the electrical connection structure provided by the embodiment of the present invention directly contacts the fine grid line 111 through the first conductive tape 121, extracts the current of the fine grid line 111, and balances the current of each first conductive tape 121 through the second conductive tape 122, omitting the main grid line and the welding tape formed with the main grid line, providing a photovoltaic module with a new structure, while being able to reduce the current transmission path, reduce current loss, and effectively improve the performance of the photovoltaic module. In addition, the current transmitted by each first conductive tape 121 is balanced by the second conductive tape 122, ensuring that the current transmitted by each battery cell 11 in the photovoltaic module is balanced and stable, so as to further improve the performance of the photovoltaic module.

[0078] In addition, since the electrical connection unit 12 in the electrical connection structure is an integrated structure with the multiple first conductive tapes 121 through the second conductive tape 122 and the second conductive tape 122 fixes the spacing between the multiple first conductive tapes 121, the multiple first conductive tapes 121 and their corresponding fine grid lines 111 can be aligned simultaneously through one positioning, without the need to align each first conductive tape 121 individually, thereby simplifying the photovoltaic module manufacturing process.

[0079] The integrated structure of the multiple electrical connection units 12 in the electrical connection structure can be formed by stamping a conductive plate through a stamping process to ensure the integrated structure of the multiple electrical connection units 12. The conductive plate can be phosphor bronze, beryllium bronze or oxygen-free copper.

[0080] Furthermore, if Figure 5 As shown, for the case where each electrical connection unit 12 includes two second conductive strips 122, the two second conductive strips 122 are disposed at both ends of the plurality of first conductive strips 121; a cutting portion 125 is disposed between two adjacent second conductive strips 122 belonging to two electrical connection units 12, wherein the cutting portion 125 is used to indicate and locate the cutting position of two adjacent electrical connection units 12. By cutting the electrical connection structure at the cutting portion 125, each electrical connection unit 12 can be formed into an independent individual, and each electrical connection unit 12, as an independent individual, connects two adjacent battery cells 11 in series.

[0081] The cutting portion 125 is provided to facilitate the positioning of the cutting position, so that the cut electrical connection units 12 are identical, thus meeting the requirements for connecting the battery cells in series.

[0082] Furthermore, for each electrical connection unit 12, there are two arrangements of the first conductive strips 121. Specifically, the first arrangement of the first conductive strips 121 is: Figures 1 to 3 , Figure 5 (B) and Figure 6As shown, in the second direction (perpendicular to the first direction) (ie, in the arrangement direction of the plurality of first conductive strips 121 ), each fine grid line first conductive strip 121 may correspond to each fine grid line 111 on one main surface of the same battery cell 11 .

[0083] The second arrangement of the first conductive strip 121 is as follows: Figure 7 and Figure 8 As shown, the first conductive strips 121 on the odd-numbered positions correspond one-to-one to the fine grid lines 111 on one main surface of the cell 11; the first conductive strips 121 on the even-numbered positions correspond one-to-one to the fine grid lines 111 on the other main surface of the cell 11. With this structure, in the process of forming the electrical connection structure, material waste can be further reduced, and the preparation cost of the electrical connection structure can be reduced.

[0084] Regardless of the first arrangement of the first conductive strips 121 or the second arrangement of the first conductive strips 121, Figures 1 to 3 , Figure 5 (B) and Figures 6 to 8 As shown, in each electrical connection unit 12, two ends of the plurality of first conductive strips 121 are provided with second conductive strips 122. More specifically, for the second arrangement of the first conductive strips 121, as shown in FIG. Figure 7 As shown, a cutting position 126 is provided between the first conductive tape 121 on the odd-numbered position and the second conductive tape 122 connected at one end; a cutting position 126 is provided between the first conductive tape 121 on the even-numbered position and the second conductive tape 122 connected at the other end, so that by cutting at the cutting position 126, the first conductive tape 121 on the odd-numbered position and the second conductive tape 122 connected at the other end thereof form an electrical connection unit 12, and the first conductive tape 121 on the even-numbered position and the second conductive tape 122 connected at one end thereof form an electrical connection unit 12. The setting of the cutting position 126 facilitates cutting two independent electrical connection units 12 from the electrical connection unit 12.

[0085] Furthermore, if Figure 2 , Figure 3 and Figure 6 As shown, the electrical connection structure may also include: at least one third conductive tape 123, wherein the third conductive tape 123 is arranged between two second conductive tapes 122, and the third conductive tape 123 intersects with multiple first conductive tapes 121, and forms an integral structure with multiple first conductive tapes 121; by cooperating with the third conductive tape 123 and the second conductive tape 122, the spacing between the first conductive tapes 121 is further improved and stabilized, so as to further facilitate the synchronous positioning of each first conductive tape 121, and can further balance the current transmission on the battery cell.

[0086] Preferably, at least one third conductive tape 123 is parallel to the second conductive tape 122 to simplify the manufacturing process of the electrical connection structure. More preferably, in the case where there are multiple third conductive tapes 123, the multiple third conductive tapes 123 are evenly spaced in the extending direction of the first conductive tape 121.

[0087] Furthermore, if Figure 4 As shown, the electrical connection unit 12 also includes: a welding layer 124, wherein the welding layer 124 is wrapped around the periphery of the first conductive tape 121 and the second conductive tape 122. The welding layer is used to increase the welding tension between the first conductive tape 121 and the second conductive tape 122 and the fine grid line 111. The thickness of the welding layer 124 may be 5μm to 25μm. For example, the thickness of the welding layer 124 is 5μm, 8μm, 10μm, 12μm, 15μm, 18μm, 20μm, 22μm, 23μm or 25μm, etc. The thickness of the welding layer 124 can be used to ensure the welding tension between the first conductive tape 121 and the second conductive tape 122 and the fine grid line 111, and to minimize the consumption of the welding layer 124 material. The welding layer may be any one of tin, tin-lead, tin-lead-bismuth, tin-bismuth-silver, tin-silver-copper, etc.

[0088] There can be two preparation processes for the welding layer 124. Specifically, the first preparation process for the welding layer 124 is: unfold the electrical connection unit 12, and sequentially undergo degreasing treatment, water washing treatment, pickling treatment, water washing treatment, electroplating treatment, water washing treatment and drying treatment. The second preparation process for the welding layer 124 is: unfold the electrical connection unit 12, and sequentially undergo annealing treatment, surface pre-coating flux treatment and hot dip plating treatment. Among them, the parameters used in each treatment process can be determined based on experimental data.

[0089] Furthermore, an embodiment of the present invention provides a method for preparing a photovoltaic module. Fig.14 As shown, the method for preparing the photovoltaic module may include:

[0090] Step S1401: alternately laying electrical connection units 12 and battery cells 11 to obtain a battery string, wherein each two adjacent battery cells 11 are connected to an electrical connection unit 12, wherein each fine grid line 111 on the battery cell 11 is placed corresponding to a first conductive strip 121 of the electrical connection unit 12;

[0091] Specifically, Figure 5 (A) The rolled electrical connection structure is unfolded, and then the electrical connection unit 12 is cut out from the electrical connection structure, and then Fig.11As shown, the electrical connection unit 12 is placed, and the battery cell 111 is covered on the electrical connection unit 12, wherein each first conductive strip 121 of the electrical connection unit 12 corresponds to each fine grid line on one main surface of the battery cell 111, and each fine grid line on the main surface of the battery cell 111 is pressed on the corresponding first conductive strip 121, and the battery cell 111 is pressed. Since each first conductive strip 121 is connected by the second conductive strip 122, each first conductive strip 121 can be positioned as a whole through a single positioning operation. The electrical connection unit 12 is further placed on the battery cell 111, and each first conductive strip 121 on the electrical connection unit 12 is positioned to each fine grid line on another main surface of the battery cell 111 through a single positioning operation, and another battery cell 11 is further covered on the electrical connection unit 12, and the electrical connection unit 12 and the battery cell 11 are sequentially stacked, thereby completing the sequential laying of each battery cell 11 and the electrical connection unit 12 of the battery string. Finally, the laid battery strings are sent to the string welding machine light box for heating into strings to complete the welding.

[0092] The laying process can be directly completed using existing processes, and during the positioning process, only one positioning operation is required to complete the synchronous positioning of each first conductive tape 121, which effectively simplifies the process operation and improves the production efficiency and yield rate of photovoltaic modules.

[0093] Step S1402: Assembling a battery string.

[0094] The battery string assembly process can be directly completed using existing processes.

[0095] Compared with the existing method of positioning each welding strip one by one, in the preparation method provided by the embodiment of the present invention, multiple first conductive strips 121 can be positioned on the battery cell 11 by one positioning, so as to effectively improve the production efficiency of photovoltaic modules.

[0096] The electrical connection structure and photovoltaic module manufacturing process provided by the embodiments of the present invention are described in detail below with reference to several embodiments.

[0097] Example 1

[0098] The copper strip is made by stamping process Figure 5 The structure shown in (B) is then electroplated to prepare a tin layer on its surface. The electroplating process is as follows: unwinding the material roll - degreasing - water washing - acid washing - water washing - tinning - water washing - drying - winding.

[0099] like Fig.11 As shown, the electrical connection unit 12 is connected from Figure 5(A) is cut into sheets from the roll - the electrical connection unit 12 is swung - the electrical connection unit 12 is positioned relative to the battery cell - the battery cell is placed to press the electrical connection unit 12 - the electrical connection unit 12 is positioned relative to the battery cell - the connection unit 12 is discharged - the pressure needle row is placed to press the battery and the electrical connection unit 12 - the electrical connection unit 12 is positioned relative to the battery cell - the battery cell is placed to press the electrical connection unit 12. After being arranged continuously in this way, it is sent to the stringing machine light box for heating into a string to complete the welding.

[0100] Example 2

[0101] The whole process is similar to that of Example 1, except that the structure of the electrical connection unit 12 prepared in this example is as follows: Figure 3 A third conductive tape 123 is arranged between the two second conductive tapes 122. On the one hand, the flatness between different welding tapes is ensured so that they will not warp or deform during the stamping, electroplating and winding processes, and it is easier to fit with the battery surface during the battery string welding and laying process; on the other hand, it can better balance the current transmission between the grid lines, reduce current loss and increase power generation.

[0102] Example 3

[0103] The preparation process is similar to that of Example 1, except that Figure 7 Before applying the structure to the photovoltaic module, the electrical connection unit 12 is punched and cut into pieces at the cutting position 126 to obtain the following Figure 8 The structure shown in Figure 8 The structure shown forms two electrical connection units 12. This structure can save the amount of copper material, and the two sets of electrical connection units 12 can be put together for stamping. Before the electrical connection units 12 are welded, the electrical connection units 12 are separated into two pieces by secondary punching. In this way, two sets of electrical connection units 12 can be punched out with the same copper strip width, reducing the amount of material used, so as to effectively reduce the production cost of the electrical connection structure and the photovoltaic module.

[0104] In summary, the embodiments of the present invention provide the following technical solutions:

[0105] Technical solution 1, a photovoltaic module, comprising: a plurality of battery strings 10, wherein:

[0106] The battery string 10 includes: a plurality of battery cells 11 and a plurality of electrical connection units 12;

[0107] Each of the electrical connection units 12 is used to connect in series the fine grid lines 111 of two adjacent battery cells 11;

[0108] The electrical connection unit 12 includes: a plurality of first conductive strips 121 arranged side by side and at intervals, and a second conductive strip 122 connected in series with the plurality of first conductive strips 121, wherein:

[0109] The plurality of first conductive strips 121 correspond one to one with the fine grid lines 111 on one main surface of the battery cell 11;

[0110] The extension direction of each of the first conductive strips 121 is consistent with the extension direction of the thin grid lines 111, and each of the first conductive strips 121 covers and connects in series two corresponding thin grid lines on two adjacent battery cells 11;

[0111] The second conductive strip 122 is disposed at the end of the first conductive strips 121 in the extending direction and is an integral structure with the first conductive strips 121 to fix the intervals between the first conductive strips 121 .

[0112] Technical Solution 2: According to the photovoltaic module of Technical Solution 1, the electrical connection unit 12 further includes: at least one third conductive tape 123, wherein:

[0113] The third conductive strip 123 is disposed between two of the second conductive strips 122 , and the third conductive strip 123 intersects with the first conductive strips 121 , and forms an integral structure with the first conductive strips 121 .

[0114] Technical solution 3: The photovoltaic module according to technical solution 2,

[0115] At least one third conductive strip 123 is parallel to the second conductive strip 122;

[0116] Preferably, in the case where there are multiple third conductive strips 123 , the multiple third conductive strips 123 are distributed at equal intervals in the extending direction of the first conductive strip 121 .

[0117] Technical solution 4: The photovoltaic module according to technical solution 1,

[0118] The first conductive strips 121 and the second conductive strips 122 of an integrated structure are formed by stamping a conductive plate through a stamping process;

[0119] and / or,

[0120] The plurality of first conductive strips 121 are perpendicular to the second conductive strips 122 .

[0121] Technical Solution 5: According to the photovoltaic module of Technical Solution 1 or 4, the electrical connection unit 12 further includes: a welding layer 124, wherein:

[0122] The welding layer 124 is wrapped around the first conductive tape 121 and the second conductive tape 122 .

[0123] Technical solution 6: A photovoltaic module according to any one of technical solutions 1 to 4,

[0124] The thickness of the first conductive tape 121 is 50 μm to 300 μm;

[0125] and / or,

[0126] The thickness of the second conductive tape 122 is 50 μm to 300 μm;

[0127] and / or,

[0128] The cross section of the first conductive strip 121 is circular, semicircular, inverted triangular or inverted trapezoidal;

[0129] and / or,

[0130] The cross section of the second conductive strip 122 is circular, semicircular, inverted triangular, or inverted trapezoidal.

[0131] Technical solution 7: The photovoltaic module according to technical solution 5,

[0132] The thickness of the welding layer 124 is 5 μm-25 μm.

[0133] Technical solution 8, an electrical connection structure, applied to a photovoltaic module, comprising: a plurality of electrical connection units 12, wherein:

[0134] The plurality of electrical connection units 12 are arranged along a first direction and are an integrated structure;

[0135] Each of the electrical connection units 12 is used to connect two adjacent cells 11 in the photovoltaic module in series;

[0136] The electrical connection unit 12 includes: a plurality of first conductive strips 121 arranged side by side and at intervals, and a second conductive strip 122 connected in series with the plurality of first conductive strips 121, wherein:

[0137] The plurality of first conductive strips 121 correspond one-to-one to the fine grid lines 111 on the cell sheet 11 of the photovoltaic module;

[0138] The extending direction of each first conductive strip 121 is consistent with the extending direction of the fine gate line 111, wherein the extending direction of the first conductive strip 121 is consistent with the first direction;

[0139] The two second conductive strips 122 are respectively disposed at two ends of the first conductive strips 121 and are integrated with the first conductive strips 121 to fix the intervals between the first conductive strips 121 .

[0140] Technical solution 9: The electrical connection structure according to technical solution 8,

[0141] For the case where each of the electrical connection units 12 includes two second conductive strips 122,

[0142] Two of the second conductive strips 122 are disposed at two ends of the plurality of the first conductive strips 121;

[0143] A cutting portion 125 is provided between two adjacent second conductive strips 122 belonging to two of the electrical connection units 12, wherein:

[0144] The cutting portion 125 is used to indicate and locate the cutting position of two adjacent electrical connection units 12 .

[0145] Technical solution 10: The electrical connection structure according to technical solution 8,

[0146] The plurality of first conductive strips 121 correspond one-to-one to the fine grid lines 111 on one main surface of the battery cell 11 .

[0147] Technical solution 11, according to the electrical connection structure of technical solution 8,

[0148] In the arrangement direction of the first conductive strips 121, the first conductive strips 121 at odd positions correspond one-to-one to the fine grid lines 111 on one main surface of the battery cell 11; the first conductive strips 121 at even positions correspond one-to-one to the fine grid lines 111 on the other main surface of the battery cell 11.

[0149] Technical solution 12. The electrical connection structure according to technical solution 11,

[0150] In each of the electrical connection units 12 , the second conductive strips 122 are disposed at both ends of the plurality of first conductive strips 121 ;

[0151] A cutting position 126 is provided between the first conductive tape 121 on the odd-numbered position and the second conductive tape 122 connected at one end;

[0152] A cutting position 126 is provided between the first conductive tape 121 on the even-numbered position and the second conductive tape 122 connected to the other end, so that by cutting at the cutting position 126, the first conductive tape 121 on the odd-numbered position and the second conductive tape 122 connected to the other end thereof form an electrical connection unit 12, and the first conductive tape 121 on the even-numbered position and the second conductive tape 122 connected to one end thereof form an electrical connection unit 12.

[0153] Technical solution 13: The electrical connection structure according to technical solution 10 further includes: at least one third conductive strip 123, wherein:

[0154] The third conductive strip 123 is disposed between two of the second conductive strips 122 , and the third conductive strip 123 intersects with the plurality of first conductive strips 121 , and forms an integral structure with the plurality of first conductive strips 121 ;

[0155] Preferably, at least one third conductive strip 123 is parallel to the second conductive strip 122;

[0156] Preferably, in the case where there are multiple third conductive strips 123 , the multiple third conductive strips 123 are distributed at equal intervals in the extending direction of the first conductive strip 121 .

[0157] Technical solution 14: The electrical connection structure according to any one of technical solutions 7 to 13,

[0158] The integrated structure of the plurality of electrical connection units 12 is formed by punching a conductive plate through a stamping process;

[0159] and / or,

[0160] The electrical connection unit 12 further includes a welding layer 124, wherein:

[0161] The welding layer 124 is wrapped around the first conductive tape 121 and the second conductive tape 122 .

[0162] Technical solution 15. A method for preparing a photovoltaic module according to any one of technical solutions 1 to 7, comprising:

[0163] Step 1, alternately laying electrical connection units 12 and battery cells 11 to obtain a battery string, wherein each two adjacent battery cells 11 are connected to one electrical connection unit 12, wherein each fine grid line 111 on the battery cell 11 is placed corresponding to a first conductive strip 121 of the electrical connection unit 12;

[0164] Step 2: assemble the battery string.

[0165] The introduction provided in the above steps is only used to help understand the method, structure and core idea of ​​the present invention. For ordinary technicians in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also belong to the scope of protection of the claims of the present invention.

Claims

1. A photovoltaic module, characterized in that: include: A plurality of battery strings (10), wherein: The battery string (10) comprises: a plurality of battery cells (11) and a plurality of electrical connection units (12); Each of the electrical connection units (12) is used to connect in series the fine grid lines (111) of two adjacent battery cells (11); The electrical connection unit (12) comprises: a plurality of first conductive strips (121) arranged side by side and at intervals, and a second conductive strip (122) connected in series with the plurality of first conductive strips (121), wherein: A plurality of the first conductive strips (121) correspond one-to-one to the fine grid lines (111) on a main surface of the battery cell (11); The extension direction of each of the first conductive strips (121) is consistent with the extension direction of the thin grid lines (111), and each of the first conductive strips (121) covers and connects in series two corresponding thin grid lines on two adjacent battery cells (11); The second conductive strip (122) is arranged at the end of the plurality of first conductive strips (121) in the extension direction, and is an integral structure with the plurality of first conductive strips (121) so as to fix the spacing between the plurality of first conductive strips (121).

2. The photovoltaic module according to claim 1, characterized in that: The electrical connection unit (12) further comprises: at least one third conductive strip (123), wherein: The third conductive strip (123) is arranged between two of the second conductive strips (122), and the third conductive strip (123) intersects with a plurality of the first conductive strips (121), and forms an integral structure with the plurality of the first conductive strips (121).

3. The photovoltaic module according to claim 2, characterized in that: At least one third conductive strip (123) is parallel to the second conductive strip (122); Preferably, in the case where there are multiple third conductive strips (123), the multiple third conductive strips (123) are distributed at equal intervals in the extension direction of the first conductive strip (121).

4. The photovoltaic module according to claim 1, characterized in that: The first plurality of conductive strips (121) and the second conductive strips (122) of an integrated structure are formed by punching a conductive plate through a stamping process; and / or, The plurality of first conductive strips (121) are perpendicular to the second conductive strips (122).

5. The photovoltaic module according to claim 1 or 4, characterized in that: The electrical connection unit (12) further comprises: a welding layer (124), wherein: The welding layer (124) is wrapped around the outer circumference of the first conductive tape (121) and the second conductive tape (122).

6. An electrical connection structure, characterized in that: Applicable to a photovoltaic module, comprising: a plurality of electrical connection units (12), wherein: The plurality of electrical connection units (12) are arranged along a first direction and the plurality of electrical connection units (12) are an integrated structure; Each of the electrical connection units (12) is used to connect in series two adjacent solar cells (11) in the photovoltaic module; The electrical connection unit (12) comprises: a plurality of first conductive strips (121) arranged side by side and at intervals, and a second conductive strip (122) connected in series with the plurality of first conductive strips (121), wherein: The plurality of first conductive strips (121) correspond one-to-one to the fine grid lines (111) on the cell sheet (11) of the photovoltaic module; The extension direction of each of the first conductive strips (121) is consistent with the extension direction of the fine gate lines (111), wherein the extension direction of the first conductive strips (121) is consistent with the first direction; Two of the second conductive strips (122) are respectively arranged at two ends of the plurality of first conductive strips (121), and are integrally structured with the plurality of first conductive strips (121) to fix the spacing between the plurality of first conductive strips (121).

7. The electrical connection structure according to claim 6, characterized in that: In the case where each of the electrical connection units (12) includes two second conductive strips (122), Two of the second conductive strips (122) are respectively arranged at two ends of the plurality of the first conductive strips (121); A cutting portion (125) is provided between two adjacent second conductive strips (122) belonging to two of the electrical connection units (12), wherein: The cutting portion (125) is used to indicate and locate the cutting positions of two adjacent electrical connection units (12).

8. The electrical connection structure according to claim 6, characterized in that: The plurality of first conductive strips (121) correspond one-to-one to the fine grid lines (111) on a main surface of the battery cell (11).

9. The electrical connection structure according to claim 6, characterized in that: In the arrangement direction of the plurality of first conductive strips (121), the first conductive strips (121) at odd positions correspond one-to-one to the fine grid lines (111) on one main surface of the battery cell (11); and the first conductive strips (121) at even positions correspond one-to-one to the fine grid lines (111) on the other main surface of the battery cell (11).

10. A method for preparing a photovoltaic module according to any one of claims 1 to 5, characterized in that: include: Step 1: alternately laying electrical connection units (12) and battery cells (11) to obtain a battery string, wherein every two adjacent battery cells (11) are connected to one electrical connection unit (12), and wherein each fine grid line (111) on the battery cell (11) is placed corresponding to a first conductive strip (121) of the electrical connection unit (12); Step 2: assemble the battery string.

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