Patent Description:
Solar energy is a clean, environment friendly, and renewable new energy, has the advantages of sufficient resources, safety, cleanliness, wide distribution, and reliable technology, and has great development prospects. With the development and application of new photovoltaic module technologies, the power generation efficiency and reliability of photovoltaic systems are effectively improved, and the cost of electricity is reduced. The photovoltaic industry requires a cell module to continuously improve performance and reduce costs, so as to drive the present application and maturity of new technologies of the cell module.

A photovoltaic module is generally made of multiple cell strings connected in series and/or in parallel, a frame, a glass panel, a back plate and sealing material are encapsulated and vacuum sealed. The multiple cell strings are connected in series and/or parallel by bus bars, and are connected to a junction box by lead wires, so as to connect the power generated by a solar cell to an external circuit, thereby conducting the current generated by the photovoltaic module.

<CIT> discloses a relevant technology regarding to a photovoltaic module, in which the circuit connection mode is suitable for a high-power module, and can meet the requirements of a diode for a circuit.

<CIT> discloses a relevant technology regarding to a photovoltaic module, in which the plurality of bypass diodes can protect all battery pieces in the photovoltaic assembly, and the output power of the photovoltaic assembly can be effectively ensured.

An object of embodiments of the present application is to provide a photovoltaic module, so as to avoid a risk of short circuit between cell strings caused by insufficient distance between two lead wires respectively connected to two ends of a diode.

In order to solve the above issue, a photovoltaic module is provided according to an embodiment of the present application, and the photovoltaic module includes: at least one cell unit group, where the cell unit group includes multiple cell strings connected in series and/or in parallel, and adjacent cell strings in the multiple cell strings are connected by a connection structure. The connection structure includes a lead-out structure, and the lead-out structure includes a main body portion, a first connecting portion and a second connecting portion that are arranged on the main body portion; the first connecting portion is connected to the second connecting portion, the first connecting portion is disposed in parallel to a length direction of the main body portion, and the second connecting portion extends out of the first connecting portion. In the length direction of the main body portion, the main body portion has a first edge, the first connecting portion is closer to the first edge than the second connecting portion.

In some embodiments, the first connecting portion covers part of the main body portion, and an orthographic projection of the first connecting portion on the main body portion has an overlapping area with the main body portion.

In some embodiments, the overlapping area coincides with the orthographic projection of the first connecting portion on the main body portion.

In some embodiments, a distance between the second connecting portion and the first edge ranges from <NUM> to <NUM>; optionally, the distance between the second connecting portion and the first edge ranges from <NUM> to <NUM>.

In some embodiments, in a direction perpendicular to the length direction of the main body portion, the main body portion is provided with a first bending line and a second bending line, the first bending line is located at a junction of the main body portion and the first connecting portion, and the second bending line is located at a junction of the first connecting portion and the second connecting portion. In a thickness direction of the main body portion, the first bending line is disposed directly opposite to the first edge, and the second bending line is disposed directly opposite to an edge of the first connecting portion facing away from the first edge.

In some embodiments, in the length direction of the main body portion, the main body portion includes a first main body portion and a second main body portion. In a thickness direction of the main body portion, the first main body portion is disposed opposite to the first connecting portion, the first main body portion and the second main body portion together form the main body portion. In the thickness direction of the main body portion, a thickness of the first main body portion is less than or equal to a thickness of the second main body portion.

In some embodiments, the first main body portion is fixedly connected to the first connecting portion in a back-to-back manner.

In some embodiments, in the thickness direction of the main body portion, a thickness of the first connecting portion is less than or equal to the thickness of the first main body portion, or the thickness of the first connecting portion is less than or equal to the thickness of the second body portion.

In some embodiments, a length of the first connecting portion is less than or equal to a height of a part of the second connecting portion that extends out of the main body portion.

In some embodiments, a ratio of the length of the first connecting portion to the height of the part of the second connecting portion that extends out of the main body portion ranges from <NUM> to <NUM>.

In some embodiments, the first connecting portion and the second connecting portion are integrally formed; the first connecting portion and the second connecting portion are fixedly connected to the main body portion.

In some embodiments, in a width direction of the main body portion, a width of the second main body portion is smaller than or equal to a width of the first main body portion.

In some embodiments, on a cross section in the thickness direction of the main body portion, the first main body portion has a cross-sectional area of the same area as a cross-sectional area of the second main body portion.

In some embodiments, each of the multiple of cell strings includes multiple solar cell pieces connected in series, and a busbar is provided on the multiple solar cell pieces. The cell unit group includes a first cell unit and a second cell unit disposed in sequence along a first direction, the first direction is an extending direction of the busbar, and the extending direction of the busbar is perpendicular to the length direction of the main body portion. The lead-out structure is disposed between the first cell unit and the second cell unit, and cell strings of the first cell unit and cell strings of the second cell unit are all connected to the main body, or the cell strings of the first cell unit and the cell strings of the second cell unit are all connected to the first connecting portion.

In some embodiments, a diode is further provided between the first cell unit and the second cell unit, and a positive electrode or a negative electrode of the diode is connected to the second connecting portion.

In some embodiments, both of the first cell unit and the second cell unit are connected to the main body portion or the first connecting portion by a solder strip. An extending direction of the solder strip intersects with the length direction of the main body portion. An end of the solder strip that comes out of the cell unit group is connected to the main body portion, or the first connecting portion.

In some embodiments, the above photovoltaic module also includes: a cover plate configured to cover an upper surface of the multiple cell strings, a back plate configured to cover a back surface of the multiple cell strings, a junction box, where a diode is disposed in the junction box, and the diode is connected to the second connecting portion, and an adhesive layer provided between the multiple cell strings and the cover plate and between the multiple cell strings and the back plate.

Compared with the prior art, the technical solutions provided according to the embodiments of the present application have the following advantages.

A photovoltaic module is provided according to the embodiments of the present application, the first connecting portion, and the second connecting portion for connecting to a diode are arranged on the main body portion of the lead-out structure. The second connecting portion is arranged close to the first edge of the main body portion in the length direction of the main body portion. The distance between the second connecting portion and the first edge ranges from <NUM> to <NUM>. In the embodiments of the present application, the first connecting portion and the second connecting portion are arranged on the lead-out structure, where the first connecting portion is arranged in parallel to the main body portion, and the second connecting portion extends out of the first connecting portion to be connected to the diode. In addition, there is a distance between the second connecting portion and the edge of the main body portion of the lead-out structure of the embodiment of the present application, so that there is a distance between two second connecting portions respectively connected to two ends of the diode, so as to avoid the risk of short circuit between cell strings, thereby ensuring the reliability of the photovoltaic module and reducing the difficulty of preparing the photovoltaic module.

It is known from the background art that cell strings are connected in series and/or in parallel by bus bars, and are connected to diodes in a junction box by lead wires. In response to the distance between the lead wires at two ends of the junction box being insufficient, it is easy to cause the risk of short circuit between the cell strings. Therefore, the design of the distance between the lead wires at two ends of the junction box is particularly important.

In a production process of a photovoltaic module, multiple solar cell pieces are generally connected in series by solder strips to form a cell string. For a conventional photovoltaic module, in some embodiments, a positive main grid and a negative main grid of a solar cell piece may be arranged on an upper surface and a back surface of the solar cell piece, respectively, that is, the positive main grid is located on the upper surface of the solar cell piece, and the negative main grid is located on the back surface of the solar cell piece. In other embodiments, the positive main grid may also be located on the back surface of the solar cell piece, and the negative main grid is located on the upper surface of the solar cell piece. The upper surface generally refers to a surface that directly receives sunlight, and the back surface generally refers to another surface opposite to the upper surface. As an example, as shown in <FIG>, a positive main grid <NUM> and a negative main grid <NUM> of a solar cell piece <NUM> are respectively located on a back surface and an upper surface of the solar cell piece <NUM>, and adjacent solar cell pieces <NUM> are connected to each other by a solder strip <NUM>. For example, one end of the solder strip <NUM> is welded to the negative main grid <NUM> on the upper surface of the solar cell piece <NUM>, and the other end of the solder strip <NUM> is welded to the positive main grid <NUM> on the back surface of another solar cell piece <NUM> adjacent to the solar cell piece <NUM>, so as to connect adjacent solar cell pieces <NUM> in series.

However, for a back-contact photovoltaic module, a positive main grid and a negative main grid of the solar cell piece <NUM> are both arranged on the back surface of the solar cell piece <NUM>, as shown in <FIG>. As an example, <FIG> show two graphic designs of a back surface of the back-contact photovoltaic module. The number of main grids on the back surface of the solar cell piece <NUM> may be an odd number or an even number. The number of main grids on the back surface of the solar cell piece <NUM> shown in <FIG> is an odd number, where the number of the positive main grids <NUM> and the number of the negative main grids <NUM> are not equal. The number of main grids on the back surface of the solar cell piece <NUM> shown in <FIG> is an even number, where the number of the positive main grids <NUM> and the number of the negative main grids <NUM> are equal.

In some embodiments, layout design of the photovoltaic module is generally performed by arranging the solar cell pieces <NUM> with small distance or negative distance, and the solar cell pieces <NUM> can be electrically connected in the form of a whole piece or multiple pieces to form multiple cell strings <NUM>. Multiple cell strings <NUM> are electrically connected in series and/or in parallel. Since the positive main grids <NUM> and the negative main grids <NUM> of the back-contact solar cell are alternately arranged, as shown in <FIG>, at an end of the cell string <NUM>, the solder strip <NUM> may be located at an edge of the solar cell piece <NUM>. As shown in <FIG>, a first bus bar <NUM> of at least one cell string <NUM> of adjacent cell strings <NUM> in a parallel connection area needs to penetrate all the main grids, and the electrical energy generated by the photovoltaic module is drawn out by a lead-out portion located at an end by the first bus bar <NUM>, and the lead-out portion is generally realized by bending the first bus bar <NUM>. Since the solder strip <NUM> may be located at an edge of the solar cell piece <NUM> in the cell string <NUM>, a distance between the lead-out portion and the solder strip <NUM> is insufficient, which will lead to the formation of overlap or the gap between adjacent lead-out portions being too insufficient. With the continuous optimization of the solar cell, the number of subsequent main grids may further increase, and the distance between the lead-out portions will be further reduced, especially for the back-contact photovoltaic module, which seriously affects the preparation of the photovoltaic module.

It should be noted that, for the back-contact photovoltaic module, except for the number of positive main grids <NUM> and the number of negative main grids <NUM> being different, except for the number of main grid lines being different, the polarities of symmetrical main grid lines on the upper and lower sides of a cutting line may be the same, or different. In addition, in a direction perpendicular to the main grid lines, there are also fine grids, and the fine grids are not in contact with the main grids of different polarities. Referring to <FIG>, which shows a schematic structural view of a back-contact solar cell piece after insulation printing is performed. The back surface of the back-contact solar cell faces upward and is subjected to the insulation printing, and the back-contact photovoltaic module after insulation printing includes the positive main grid <NUM>, the negative main grid <NUM>, a positive electrode fine grid <NUM>, a negative electrode fine grid <NUM>, and an insulating glue <NUM>, where a printing height of the insulating glue <NUM> is greater than or equal to twice of a height of the fine grid.

As an example, <FIG> shows a schematic view of the overall structure of a back-contact photovoltaic module. The existing back-contact photovoltaic module generally adopts a half-piece model. As shown in <FIG>, the solar cell piece <NUM> is a cell piece segment; where the cell piece segment may be a cell piece half-segment formed by evenly cutting a cell base piece into two equal pieces along a first direction, or may be a cell piece segment formed by cutting the cell base piece into N pieces along the first direction, where N≥<NUM> and N is a positive integer. For example, the solar cell piece <NUM> may be a <NUM>/<NUM> cell piece segment formed by evenly cutting the cell base piece into <NUM> pieces along the first direction, or the solar cell piece <NUM> may also be a quarter cell piece segment formed by evenly cutting the cell base piece into <NUM> pieces along the first direction, or the solar cell piece <NUM> may also be <NUM>/<NUM> cell piece segment formed by evenly cutting the cell base piece into <NUM> pieces along the first direction.

In a preparation process of the back-contact photovoltaic module, adjacent cell piece segments are connected in series and then connected in parallel to form a photovoltaic module. In order to realize the series connection between different cell strings, it is necessary to ensure that the polarities of adjacent cell strings <NUM> are opposite. Therefore, it is necessary to rotate another cell string <NUM> adjacent to the cell string <NUM> by <NUM> degrees to ensure that the polarities of the adjacent cell strings <NUM> are opposite. The polarities of adjacent cell strings <NUM> are shown in the circuit diagram of the photovoltaic module in <FIG>. After that, a second bus bar <NUM> is welded between every two cell strings <NUM> to realize the series connection of the two cell strings <NUM>. As shown in <FIG>, two adjacent columns of cell strings <NUM> (direction of columns is shown as the second direction) are connected in series by the second bus bars <NUM> located at edges of the cell strings <NUM> along the second direction, to form a cell unit. The cell unit includes a first cell unit <NUM> and a second cell unit <NUM> arranged in sequence along the second direction. <FIG> shows a case where the number of the first cell units <NUM> and the second cell units <NUM> are both three, each of the three first cell units <NUM> and the three second cell units <NUM> includes two of the cell strings <NUM>, and each of the two cell strings <NUM> includes six solar cell pieces <NUM> connected in series.

Reference is made back to <FIG>, the number of the second bus bars <NUM> of the photovoltaic module is six, where three of the six second bus bars <NUM> are located at the top of the first cell unit <NUM> along the second direction, so as to realize the connection of two cell strings <NUM> in the first cell unit <NUM>, and the other three of the six second bus bars <NUM> are located at the bottom of the second cell unit <NUM> along the second direction, so as to realize the connection of the two cell strings <NUM> in the second cell unit <NUM>. The first cell unit <NUM> and the second cell unit <NUM> are connected in parallel by the first bus bar <NUM>. In order to ensure the same polarity of the cell strings <NUM> in the first cell unit <NUM>, and the same polarity of the cell strings <NUM> the second cell unit <NUM>, the first cell unit <NUM> and/ or the second cell unit <NUM> is rotated by <NUM> degrees, and the connection between the first cell unit <NUM> and the second cell unit <NUM> is realized by the first bus bar <NUM> disposed between the first cell unit <NUM> and the second cell unit <NUM>, to form the cell unit. Multiple groups of cell units are connected in series or in parallel to form the photovoltaic module.

Generally, the photovoltaic module further includes a junction box, which is arranged on the back plate of the photovoltaic module; the diode <NUM> is arranged in the junction box, and the junction box is generally located between adjacent cell units. A lead-out wire extends out of an end of the first bus bar <NUM> for connecting the first cell unit <NUM> to the second cell unit <NUM>, by which the connection with one end of the diode <NUM> is realized, and the other end of the diode <NUM> is connected to the lead-out wire of the first bus bar <NUM> for connecting adjacent cell unit, so that the connection of adjacent cell units is realized. As shown in <FIG>, every two cell strings <NUM> are connected in series to form the first cell unit <NUM> or the second cell unit <NUM>, and an output end of the first cell unit <NUM> and an output end of the second cell unit <NUM> are both connected to the diode <NUM>, that is, the electric energy generated by the cell pieces is drawn out by a lead-out portion <NUM> of the first bus bar <NUM>, and the lead-out portion <NUM> is connected to the diode <NUM>. As shown in <FIG>, the lead-out portion <NUM> is generally formed by bending the first bus bar <NUM>. Considering the bending radius of the first bus bar <NUM> and the operability of welding, a distance between the lead-out portion <NUM> of the first bus bar <NUM> and the solder strip <NUM> is generally <NUM>. However, by adopting this solution, the lead-out portions <NUM> arranged oppositely on the adjacent first bus bars <NUM> in the photovoltaic module may form overlapping, or a distance between the adjacent lead-out portions <NUM> may be insufficient. As shown in <FIG>, the distance between the lead-out portions <NUM> arranged oppositely on the adjacent first bus bars <NUM> is excessively small, and a distance between the solder strips <NUM> located at the edge of the solar cell piece <NUM> is also excessively small. With the continuous optimization of the back-contact solar cell, the number of subsequent main grids may be further increased, and the distance between the two oppositely arranged lead-out portions <NUM> will be further reduced, which undoubtedly increases the risk of short circuit between the cell strings <NUM> and seriously affects the preparation of the back-contact photovoltaic module.

In order to solve the above technical problem, referring to <FIG>, a photovoltaic module is provided according to an embodiment of the present application, and the photovoltaic module includes: at least one cell unit group <NUM>, where the cell unit group <NUM> includes multiple cell strings <NUM> connected in series and/or in parallel, and adjacent cell strings <NUM> in the multiple cell strings <NUM> are connected by a connection structure. The connection structure includes a lead-out structure <NUM>, and the lead-out structure <NUM> includes a main body portion <NUM>, a first connecting portion <NUM> and a second connecting portion <NUM> that are arranged on the main body portion <NUM>. The first connecting portion <NUM> is connected to the second connecting portion <NUM>, the first connecting portion <NUM> is disposed in parallel to a length direction of the main body portion <NUM>, and the second connecting portion <NUM> extends out of the first connecting portion <NUM>. In the length direction of the main body portion <NUM>, the main body portion <NUM> has a first edge <NUM>, the second connecting portion <NUM> is closer to the first edge <NUM> relative to the first connecting portion <NUM>, and a distance between the second connecting portion <NUM> and the first edge <NUM> ranges from <NUM> to <NUM>.

It should be noted that, as shown in <FIG>, the connection structure includes the lead-out structure <NUM> and the second bus bar <NUM>, where the second bus bar <NUM> are arranged in two groups, and the two groups of second bus bars <NUM> are disposed at an upper edge and a lower edge of the photovoltaic module along the second direction, respectively, to realize the series connection between adjacent cell strings <NUM>. The lead-out structure <NUM> is arranged between the cell units formed after every two groups of cell strings <NUM> are connected in series, and is configured to lead the current of the cell units out and connect to the diode <NUM>, so as to realize the connection of adjacent cell units.

In some embodiments, the distance between the second connecting portion <NUM> and the first edge <NUM> may be <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>. Preferably, the distance between the second connecting portion <NUM> and the first edge <NUM> ranges from <NUM> to <NUM>.

Referring to <FIG>, which are both enlarged views at A in <FIG>. As an example, <FIG> shows a schematic view of where the first connecting portion <NUM> and the second connecting portion <NUM> are arranged on the main body portion <NUM>. The photovoltaic module shown in <FIG> is taken as an example, it can be seen from <FIG> that the photovoltaic module includes three cell unit groups <NUM>, and a junction box is arranged between every two adjacent cell unit groups <NUM>, and the lead-out structure <NUM> extends out of the first connecting portion <NUM> and the second connecting portion <NUM> to be connected to the diode <NUM> in the junction box. It should be noted that the solar cell piece <NUM> shown in <FIG> and <FIG> is a cell piece half-segment. As shown in <FIG>, the number of the lead-out structures <NUM> are four, all of which are located between two cell units arranged in sequence along the second direction, and the lead-out structure <NUM> close to the left edge of the photovoltaic module is provided with the first connecting portion <NUM> and the second connecting portion <NUM> for cooperatively connecting to a same diode <NUM> with the adjacent cell unit. The first connecting portion <NUM> and the second connecting portion <NUM> are disposed close to the first edge <NUM> of the lead-out structure <NUM> relative to the main body portion <NUM>. In this case, the first edge <NUM> is the right edge of the lead-out structure <NUM>. The lead-out structure <NUM> close to the right edge of the photovoltaic module is provided with the first connecting portion <NUM> and the second connecting portion <NUM>. In order to cooperatively connect to the same diode <NUM> with the adjacent cell unit, the first connecting portion <NUM> and the second connecting portion <NUM> are disposed close to the first edge <NUM> of the lead-out structure <NUM> relative to the main body portion <NUM>. In this case, the first edge <NUM> is the left edge of the lead-out structure <NUM>. The number of the first edges <NUM> on the main body portion <NUM> may be two. As shown in <FIG>, each of the two lead-out structures <NUM> located in the middle of the photovoltaic module is provided with two connecting portions, and the two connecting portions are arranged at two edges close to two side of the main body portion <NUM> relative to the middle of the main body portion <NUM>. In this case, the number of the first edges <NUM> is two, which are the two edges of the main body portion <NUM> along the length direction. In order to ensure that the second connecting portion <NUM> and the adjacent cell unit are cooperatively connected to the same diode <NUM>, the second connecting portion <NUM> is close to the first edge <NUM> on two sides of the main body portion <NUM> relative to the first connecting portion <NUM>, and the distance between the second connecting portions <NUM> and the first edge <NUM> ranges from <NUM> to <NUM>.

<FIG> shows a schematic view in which the first connecting portion <NUM> is arranged close to the edge of the main body portion <NUM>. As an example, <FIG> shows a case where the first connecting portion <NUM> can also be arranged close to the edge of the main body portion <NUM>, a safe distance between second connecting portions <NUM> of the adjacent cell units is formed to avoid the risk of short circuit of the cell unit.

It should be noted that, as an example, <FIG> shows that the photovoltaic module includes three cell unit groups <NUM>, and each of the cell unit groups <NUM> includes two cell units arranged in sequence along the second direction, and each of the cell units includes two cell strings <NUM> connected in series, and each of the cell strings <NUM> includes seven solar cell pieces <NUM> connected in series. The number of solar cell pieces <NUM> in each of the cell strings <NUM>, and the number of cell strings <NUM> in each of the cell units, and the number of the cell unit groups <NUM> is not limited in the embodiments of the present application.

<FIG> shows a schematic view of a lead-out structure provided according to an embodiment of the present application. As shown in <FIG>, the first connecting portion <NUM> is closer to the first edge <NUM> relative to the second connecting portion <NUM>. An end of the first connecting portion <NUM> close to the first edge <NUM> is connected to the first edge <NUM>, and an end of the first connecting portion <NUM> away from the first edge <NUM> is connected to the second connecting portion <NUM>. A distance between the second connecting portion <NUM> and the first edge <NUM> ranges from <NUM> to <NUM>, that is to say, a distance between the end of the first connecting portion <NUM> away from the first edge <NUM> and the first edges <NUM> ranges from <NUM> to <NUM>.

Preferably, the distance between the second connecting portion <NUM> and the first edge <NUM> ranges from <NUM> to <NUM>. Generally, in order to ensure a safe distance between the second connecting portion <NUM> and the first edge <NUM>, avoid the risk of short circuit of the cell unit, and ensure the reliability of the photovoltaic module, the distance between the second connecting portion <NUM> and the first edge <NUM> is greater than <NUM>. In some embodiments, the distance between the second connecting portion <NUM> and the first edge <NUM> may be <NUM>, <NUM>, <NUM>, <NUM> or <NUM>.

In some embodiments, the first connecting portion <NUM> covers part of the main body portion <NUM>, and an orthographic projection of the first connecting portion <NUM> on the main body portion <NUM> has an overlapping area with the main body portion <NUM>.

Reference is continuously made to <FIG>, the first connecting portion <NUM> covers a part of a surface of the main body portion <NUM> close to the first edge <NUM>, and a portion of the first connecting portion <NUM> covering the main body portion <NUM> is referred to as a covering portion. In response to a width of the first connecting portion <NUM> being greater than a width of the covering portion, the area of the orthographic projection of the first connecting portion <NUM> in the direction perpendicular to the main body portion <NUM> is greater than the area of the covering portion. In response to the width of the first connecting portion <NUM> being smaller than that of the covering portion, the area of the orthographic projection of the first connecting portion <NUM> in the direction perpendicular to the main body portion <NUM> is smaller than the area of the covering portion, and the orthographic projection of the first connecting portion <NUM> on the main body portion <NUM> is located inside the covering portion.

In some embodiments, the overlapping area coincides with the orthographic projection of the first connecting portion <NUM> on the main body portion <NUM>.

Reference is continuously made to <FIG>, in response to the width of the first connecting portion <NUM> being equal to the width of the covering portion, and a length of the first connecting portion <NUM> being equal to a length of the covering portion, an orthographic projection of the covering portion on the main body portion <NUM> perfectly coincides with the orthographic projection of the first connecting portion <NUM> on the main body portion <NUM>, that is, the overlapping area coincides with the orthographic projection of the first connecting portion <NUM> on the main body portion <NUM>.

In some embodiments, the end of the first connecting portion <NUM> away from the first edge <NUM> is connected to the second connecting portion <NUM>, the first connecting portion <NUM> is integrally formed with the second connecting portion <NUM> and the main body portion <NUM>. respectively. As shown in <FIG>, the end of the first connecting portion <NUM> close to the first edge <NUM> is connected to the first edge <NUM> of the main body portion <NUM>, and the end of the first connecting portion <NUM> away from the first edge <NUM> is connected to the second connecting portion <NUM>. The first connecting portion <NUM> is integrally formed with the second connecting portion <NUM> and the main body portion <NUM>, respectively. A bus strip can be used as the main body portion <NUM>, which is bent to obtain the lead-out structure <NUM>.

In some embodiments, in a direction perpendicular to the length direction of the main body portion <NUM>, the main body portion <NUM> is provided with a first bending line <NUM> and a second bending line <NUM>, the first bending line <NUM> is located at a junction of the main body portion <NUM> and the first connecting portion <NUM>, and the second bending line <NUM> is located at a junction of the first connecting portion <NUM> and the second connecting portion <NUM>. In a thickness direction of the main body portion <NUM>, the first bending line <NUM> is disposed directly opposite to the first edge <NUM>, and the second bending line <NUM> is disposed directly opposite to the edge of the first connecting portion <NUM> facing away from the first edge <NUM>.

In response to the main body portion <NUM>, the first connecting portion <NUM> and the second connecting portion <NUM> being integrally formed, a bus strip is served as the main body portion <NUM>. Referring to <FIG>, the strip-shaped main body portion <NUM> is sequentially provided with the first bending line <NUM> and the second bending line <NUM>. The main body portion <NUM> is bent first along the direction of the first bending line <NUM> towards the main body portion <NUM>, so that the main body portion <NUM> located on the right side of the first bending line <NUM> partially overlaps with the main body portion <NUM> located on the left side of the first bending line <NUM>. In this case, the second bending line <NUM> is located on the bent part covering part of the surface of the main body portion <NUM>, and the bent part is bent again along the second bending line <NUM> of the main body portion <NUM>, as shown in <FIG>. Finally, the lead-out structure as shown in <FIG> is obtained, the first connecting portion <NUM> covering part of the main body portion <NUM> and the second connecting portion <NUM> perpendicular to the first connecting portion <NUM> are formed, and the first connecting portion <NUM> and the main body portion <NUM> are welded and fixed, so that the lead-out structure <NUM> is obtained.

Reference is continuously made to <FIG>, in the length direction of the main body portion <NUM>, the main body portion <NUM> includes a first main body portion 21a and a second main body portion 21b. In a thickness direction of the main body portion <NUM>, the first main body portion <NUM> is disposed opposite to the first connecting portion <NUM>, the first main body portion 21a and the second main body portion 21b together form the main body portion <NUM>. In the thickness direction of the main body portion <NUM>, a thickness of the first main body portion 21a is less than or equal to a thickness of the second main body portion 21b.

In some embodiments, in order to avoid excessive thickness of the main body portion <NUM> after the first connecting portion <NUM> is welded, which may result in a lack of glue in the subsequent connection with the solder strip <NUM>, a thickness of the first main body portion 21a of the main body portion <NUM> facing toward the first connecting portion <NUM> is appropriately reduced to avoid excessive thickness of a part of the main body portion <NUM> due to the overlapping of the first main body portion 21a and the first connecting portion <NUM> after the main body portion <NUM> is welded with the first connecting portion <NUM>, so as to avoid the effect on the layout of the photovoltaic module.

Preferably, the thickness of the first main body portion 21a is smaller than the thickness of the second main body portion 21b. Since the first main body portion 21a and the first connecting portion <NUM> are arranged overlappingly, in order to avoid the excessive thickness of the first connecting portion <NUM> and the first main body portion 21a of the lead-out structure <NUM> after being bent, which affects the performance of the lead-out structure <NUM>, the thickness of the first main body portion 21a is reduced. As shown in <FIG>, the thickness of the first main body portion 21a may be half of the thickness of the second main body portion 21b, and the thickness of the first connecting portion <NUM> is approximately equal to the thickness of the first main body portion 21a. In this case, the overall thickness of the main body portion 21a and the first connecting portion <NUM> after overlapping is approximately equal to the thickness of the second main body portion 21b, so as to ensure the overall performance of the lead-out structure <NUM>. In this case, it is also beneficial to the overall layout of the photovoltaic module. After the second connecting portion <NUM> is arranged on the main body portion <NUM>, the thickness of the main body portion <NUM> will not be increased excessively, so as to ensure that the photovoltaic module can be arranged on the original layout.

In some embodiments, the first main body portion 21a is fixedly connected to the first connecting portion <NUM> in a back-to-back manner.

Reference is continuously made to <FIG>, in order to ensure the integrity of the lead-out structure <NUM>, the first main body portion 21a is fixedly attached to the first connecting portion <NUM> in a back-to-back manner, that is, an upper surface of the first main body portion 21a is attached to a lower surface of the first connecting portion <NUM>, and the upper surface of the first main body portion 21a is welded to the lower surface of the first connecting portion <NUM> by soldering, so as to fix the first main body portion 21a and the first connecting portion <NUM> together, thereby fixing the main body portion <NUM> and the lead-out structure <NUM> together.

Referring to <FIG>, in some embodiments, in the length direction of the main body portion <NUM>, the main body portion <NUM> includes a first main body portion 21a and a second main body portion 21b. In a thickness direction of the main body portion <NUM>, the first main body portion <NUM> is disposed opposite to the first connecting portion <NUM>, the first main body portion 21a and the second main body portion 21b together form the main body portion <NUM>. In the thickness direction of the main body portion <NUM>, a thickness of the first main body portion 21a is less than or equal to a thickness of the second main body portion 21b.

In some embodiments, as shown in <FIG>, in the width direction of the main body portion <NUM>, a width of the second main body portion 21b is equal to a width of the first main body portion 21a.

In some embodiments, the first connecting portion <NUM> and the second connecting portion <NUM> are located on the first main body portion 21a, and orthographic projections of the second main body portion 21b, the first connecting portion <NUM> and the second connecting portion <NUM> on the main body portion <NUM> have no overlapping area. Specifically, in the length direction of the main body portion <NUM>, a distance between the orthographic projection of the second main body portion 21b on the main body portion <NUM> and the orthographic projections of the first connecting portion <NUM> and the second connecting portion <NUM> on the main body portion <NUM> is greater than or equal to <NUM> and less than or equal to <NUM>, to avoid the risk of short circuit of the solar cell, so as to ensure the reliability of the photovoltaic module.

As shown in <FIG>, an area where the first connecting portion <NUM> overlaps with the main body portion <NUM> is the first main body portion 21a, an area where the first connecting portion <NUM> does not overlap with the main body portion <NUM> is the second main body portion 21b, and the first main body portion 21a and the second main body portions 21b together form the main body portion <NUM>. In order to avoid excessive thickness of the main body portion <NUM> after the first connecting portion <NUM> is welded to the main body portion <NUM>, which may result in a lack of glue in the subsequent connection with the solder strip <NUM>, a thickness of the first main body portion 21a of the main body portion <NUM> facing toward the first connecting portion <NUM> is appropriately reduced to avoid excessive thickness of a part of the main body portion <NUM> due to the overlapping of the first main body portion 21a and the first connecting portion <NUM> after the main body portion <NUM> is welded with the first connecting portion <NUM>, so as to avoid the effect on the layout of the photovoltaic module.

Preferably, the thickness of the first main body portion 21a is smaller than the thickness of the second main body portion 21b. Since a first sub-connecting portion 211a and the first main body portion 21a are welded together in two layers, in order to prevent the thickness of the main body portion <NUM> from being excessive after the first sub-connecting portion 211a and the first main body portion 21a are welded together, as shown in <FIG>, the thickness of the first main body portion 21a is one third of the thickness of the second main body portion 21b, and a thickness of the first sub-connecting portion 211a is one third of the thickness of the second main body portion 21b, so that the thickness of the first sub-connecting portion 211a is approximately equal to the thickness of the first main body portion 21a. In this case, it can be ensured that the total overlapping thickness of the first sub-connecting portions 211a and the first main body portion <NUM> is approximately equal to the thickness of the second main body portion 21b, so as to ensure that the overall performance of the lead-out structure <NUM>, thereby preventing the layout of the photovoltaic module from being adversely affected.

In other embodiments, the lead-out structure provided according to the embodiments of the present application can also be formed by other bending methods, the lead-out structure shown in <FIG> can also be obtained by bending the lead-out structure shown in <FIG> by three times. Specifically, the first bending is performed by bending a part of the bus strip located at the right side of the first bending line <NUM> along the first bending line <NUM> to above of the main body portion <NUM> (inwardly bending). The second bending is performed by bending a part of the bus strip located above the main body portion 21a along the second bending line <NUM>, so that the bent bus strip is parallel to the main body portion <NUM>. The third bending is performed by bending the bus strip bent in the second bending along the third bending line <NUM> (upwardly bending) to form the second connecting portion <NUM> extending out of the main body portion <NUM>. In this case, the preparation of the lead-out structure can be more convenient, and the overall stability of the lead-out structure <NUM> can be ensured.

Specifically, referring to <FIG>, in a direction perpendicular to the length direction of the main body portion <NUM>, the first bending line <NUM> is arranged at a junction of the main body portion <NUM> and the first connecting portion <NUM>, and the first connecting portion <NUM> includes two layers of the first sub-connecting portion 211a. The second bending line <NUM> is arranged at a junction of the two first sub-connecting portions 211a, and the third bending line <NUM> is arranged at a junction of the first sub-connecting portion 211a and the second connecting portion <NUM>. In the thickness direction of the main body portion <NUM>, the first bending line <NUM> and the third bending line <NUM> both face toward the first edge <NUM>, and the second bending line <NUM> faces toward the edge of the first connecting portion <NUM> away from the first edge <NUM>. The first connecting portion <NUM> formed by bending the main body portion <NUM> is located on the upper surface of the main body portion <NUM>, the first connecting portion <NUM> is parallel to the main body portion <NUM>, and the second connecting portion <NUM> is perpendicular to the first connecting portion <NUM>.

As shown in <FIG>, in the embodiments of the present application, the first connecting portion <NUM> and the second connecting portion <NUM> are arranged on the main body portion <NUM>. The first connecting portion <NUM> is parallel to the length direction of the main body portion <NUM>, and the second connecting portion <NUM> extends out of the first connecting portion <NUM>. In some embodiments, the first connecting portion <NUM> is perpendicular to the second connecting portion <NUM>. An end of the second connecting portion <NUM> extending out of the first connecting portion <NUM> is connected to the diode <NUM>, and an end of the solder strip <NUM> welded on the solar cell piece <NUM> extending out of the solar cell piece <NUM> is connected to the lead-out structure <NUM> except for the second connecting portion <NUM>. That is to say, the end of the solder strip <NUM> extending out of the solar cell piece <NUM> may be connected to the main body portion <NUM>, or may be connected to the first connecting portion <NUM>.

In some embodiments, in order to avoid excessive thickness of the main body portion <NUM> after the first connecting portion <NUM> and the second connecting portion 212are welded, resulting in a lack of glue in the subsequent connection with the solder strip <NUM>, the thickness of the first main body portion 21a of the main body portion <NUM> is reduced to ensure the thickness of the first main body portion 21a after the main body portion <NUM> is welded to the first connecting portion <NUM> and the second connecting portion <NUM>.

It can be understood that the lead-out structure <NUM> provided according to the embodiments of the present application can also be used for the connection of adjacent cell strings of the back-contact photovoltaic module shown in <FIG>. As shown in <FIG>, the back-contact photovoltaic module includes multiple cell unit groups <NUM> connected in parallel, and each of the multiple cell unit groups <NUM> includes a first cell unit <NUM> and a second cell unit <NUM>, and each of the first cell unit <NUM> and the second cell unit <NUM> includes two cell strings <NUM> connected in series. The two cell strings <NUM> of the first cell unit <NUM> are connected together by a second bus bar <NUM> located on the top of the first cell unit <NUM>, and the two cell strings <NUM> of the second cell unit <NUM> are connected together by a second bus bar <NUM> located at the bottom of the first cell unit <NUM>. The lead-out structure <NUM> is disposed between the first cell unit <NUM> and the second cell unit <NUM>, and the first cell unit <NUM> and the second cell unit <NUM> are also connected by the lead-out structure <NUM>. The adjacent lead-out structures <NUM> are respectively connected to the diode <NUM> by the second connecting portions <NUM> arranged on the main body portions <NUM>.

The lead-out structure <NUM> provided according to the embodiments of the present application can also be configured to connect cell strings of the conventional photovoltaic module. As shown in <FIG>, the lead-out structure <NUM> is arranged between the first cell unit <NUM> and the second cell unit <NUM>, and the cell string <NUM> of first cell unit <NUM> and the cell string <NUM> of the second cell unit <NUM> are connected together by the lead-out structure <NUM>.

In some embodiments, in the thickness direction of the main body portion <NUM>, the thickness of the first connecting portion <NUM> is less than or equal to the thickness of the first main body portion 21a, or the thickness of the first connecting portion <NUM> is less than or equal to the thickness of the second main body portion 21b.

It should be noted that, the thickness of the first connecting portion <NUM> may be equal to the thickness of the first main body portion 21a, and may also be equal to the thickness of the second main body portion 21b.

Preferably, the thickness of the first main body portion 21a may range from <NUM> to <NUM>, for example, the thickness of the first main body portion 21a may be <NUM>, <NUM>, <NUM>, <NUM> or <NUM>. The thickness of the second main body portion 21b may range from <NUM> to <NUM>, for example, the thickness of the second main body portion 21b may be <NUM>, <NUM>, <NUM>, <NUM> or <NUM>.

In some embodiments, the length of the first connecting portion <NUM> is less than or equal to the height of a part of the second connecting portion <NUM> extending out of the main body portion <NUM>.

For example, the length of the first connecting portion <NUM> is approximately range from <NUM>% to <NUM>% of the length of the main body portion <NUM>. In a preferred embodiment, the length of the first connecting portion <NUM> is less than or equal to the height of the part of the second connecting portion <NUM> extending out of the main body portion <NUM>, so as to prevent the overall thickness of the main body portion <NUM> from being affected due to the excessive length of the first connecting portion <NUM>.

In some embodiments, a ratio of the length of the first connecting portion <NUM> to the height of the part of the second connecting portion <NUM> extending out of the main body portion <NUM> ranges from <NUM> to <NUM>. For example, the ratio of the length of the first connecting portion <NUM> to the height of the part of the second connecting portion <NUM> extending out of the main body portion <NUM> may be <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>. Preferably, the ratio of the length of the first connecting portion <NUM> to the height of the part of the second connecting portion <NUM> extending out of the main body portion <NUM> is <NUM>.

For example, the height of the part of the second connecting portion <NUM> extending out of the main body portion <NUM> may be <NUM>, and the length of the first connecting portion <NUM> along the length direction of the main body portion <NUM> approximately ranges from <NUM> to <NUM>. Preferably, the length of the first connecting portion <NUM> along the length direction of the main body portion <NUM> ranges from <NUM> to <NUM>.

In some embodiments, the first connecting portion <NUM> and the second connecting portion <NUM> are integrally formed, and the first connecting portion <NUM> and the second connecting portion <NUM> are fixedly connected to the main body portion <NUM>.

Preferably, the first connecting portion <NUM> and the second connecting portion <NUM> can be realized by bending a bus strip, and the first connecting portion <NUM> and the second connecting portion <NUM> are welded on the main body portion <NUM>.

In some embodiments, the first connecting portion <NUM> and the second connecting portion <NUM> are separate structures. After the first connecting portion <NUM> and the second connecting portion <NUM> are welded together, and the first connecting portion <NUM> and the second connecting portion <NUM> are welded to the main body portion <NUM>.

In some embodiments, in the width direction of the main body portion <NUM>, the width of the second main body portion 21b is smaller than or equal to the width of the first main body portion 21a.

In some embodiments, as shown in <FIG>, in the thickness direction of the main body portion <NUM>, the thickness of the first main body portion 21a is equal to the thickness of the second main body portion 21b.

In other embodiments, <FIG> show top views of the main body portion <NUM>. As can be seen from <FIG>, in the width direction of the main body portion <NUM>, the width of the first main body portion 21a is greater than the width of the second main body portion 21b. As shown in <FIG>, the width of the second main body portion 21b gradually decreases in the direction away from the left edge of the first main body portion 21a, and the width of the second main body portion 21b gradually decreases in the direction away from the right edge of the first main body portion 21a.

In other embodiments, in the thickness direction of the main body portion <NUM>, the thickness of the first main body portion 21a is smaller than the thickness of the second main body portion 21b. As an example, <FIG> show cross-sectional views of the main body portion <NUM>. As shown in <FIG>, the width of the second main body portion 21b gradually increases in the direction away from the left edge of the first main body portion 21a, and the width of the second main body portion 21b gradually increases in the direction away from the right edge of the first main body portion 21a. In the main body portion <NUM> of the embodiments of the present application, the thickness of the first main body portion 21a is smaller than the thickness of the second main body portion 21b, and the width of the second main body portion 21b is smaller than the width of the first main body portion 21a, which is beneficial to the overall layout of the photovoltaic module. In a case where the first main body portion 21a of the main body portion <NUM> is welded to the first connecting portion <NUM> or the second connecting portion <NUM>, widths of two ends of the main body portion <NUM> will not be increased to ensure that the photovoltaic module is arranged on the original layout.

In some embodiments, in the cross section of the main body portion <NUM> along the thickness direction, the area of the cross section of the first main body portion 21a is equal to the area of the cross section of the second main body portion 21b.

In some embodiments, the area of the cross section of the first main body portion 21a is substantially equal to the area of the cross section of the second main body portion 21b. Due to process reasons, the area of the cross section of the first main body portion 21a may vary by <NUM>% from the area of the cross section of the second main body portion 21b. It should be noted that the bus bar generally includes a solder core and a coating covering the outside of the solder core. In the cross section of the main body portion <NUM> along the thickness direction, the area of the cross section of the solder core of the first main body portion 21a is equal to the area of the cross section of the solder core of the second main body portion 21b.

In some embodiments, as shown in <FIG>, the cell string <NUM> includes multiple solar cell pieces <NUM> connected in series, and the solar cell pieces <NUM> are provided with bus bars. The cell unit group <NUM> includes the first cell unit <NUM> and the second cell unit <NUM> arranged in sequence along the first direction. The first direction is the extending direction of the main grid, and the extending direction of the main grid intersects the length direction of the main body portion <NUM>. The lead-out structure <NUM> is arranged between the first cell unit <NUM> and the second cell unit <NUM>, and the cell strings <NUM> of the first cell unit <NUM> and the cell strings <NUM> of the second cell unit <NUM> are both connected to the main body portion <NUM>, or the first connecting portion <NUM>.

It should be noted that the extending direction of the busbar intersects the longitudinal direction of the main body portion <NUM>. Here, the extending direction of the busbar and the longitudinal direction of the main body portion <NUM> may be perpendicular, or may be substantially perpendicular.

In some embodiments, the diode <NUM> is further provided between the first cell unit <NUM> and the second cell unit <NUM>, a positive electrode of the diode <NUM> is connected to the second connecting portion <NUM>, or a negative electrode of the diode <NUM> is connected to the second connecting portion <NUM>.

Reference is made to <FIG>, which is a circuit diagram corresponding to the photovoltaic module shown in <FIG>. It can be seen from <FIG> that the diode <NUM> is disposed between the first cell unit <NUM> and the second cell unit <NUM>, and two ends of the diode <NUM> are respectively connected to the cell strings <NUM> in the adjacent cell units. The lead-out structure <NUM> is disposed between the first cell unit <NUM> and the second cell unit <NUM>, and one end of each of adjacent second connecting portions <NUM> extending out of the first connecting portion <NUM> is connected to the positive electrode and the negative electrode of the diode <NUM>, respectively.

Referring to <FIG>, in some embodiments, the first cell unit <NUM> and the second cell unit <NUM> are both connected to the main body portion <NUM> or the first connecting portion <NUM> by the solder strip <NUM>. The extending direction of the solder strip <NUM> intersects with the length direction of the main body portion <NUM> The directions intersect. An end of the solder strip <NUM> extending out of the cell unit group <NUM> is connected to the main body portion <NUM>, or the first connecting portion <NUM>.

Referring to <FIG>, in some embodiments, the above photovoltaic module further includes: a cover plate <NUM> configured to cover an upper surface of the multiple cell strings <NUM>, a back plate <NUM> configured to cover a back surface of the multiple cell strings <NUM>. For the back-contact photovoltaic module, the solder strip <NUM> is arranged on the back surface of the solar cell piece <NUM>, to connect the positive main grid to the negative main grid. A junction box is generally arranged on the back plate <NUM>, the diode <NUM> is disposed in the junction box, and the diode <NUM> is connected to the second connecting portion. An adhesive layer provided between the multiple cell strings <NUM> and the cover plate <NUM> and between the multiple cell strings <NUM> and the back plate <NUM>.

In other embodiments, as shown in <FIG>, for a conventional photovoltaic module, the positive main grid and the negative main grid are connected together by the solder strip <NUM>. One end of the solder strip <NUM> is located on the back surface of the solar cell piece <NUM>, and the other end of the solder strip <NUM> is located on the upper surface of the solar cell piece <NUM>.

Specifically, in some embodiments, multiple cell strings <NUM> are connected by a connecting structure. An encapsulation layer covers a front surface and a back surface of the solar cell. Specifically, the adhesive layer includes a first adhesive layer <NUM> and a second adhesive layer <NUM>. The first adhesive layer <NUM> is disposed between the cell string <NUM> and the cover plate <NUM> to fix of the cell string <NUM> and the cover plate <NUM>. The second adhesive layer is disposed between the cell strings <NUM> and the back plate <NUM> to fix the cell string <NUM> and the back plate <NUM>. In some embodiments, the cover plate <NUM> may be embodied as a light-transmitting cover plate, such as a glass cover plate, a plastic cover plate, or the like.

A photovoltaic module is provided according to the embodiments of the present application, the first connecting portion <NUM>, and the second connecting portion <NUM> for connecting to the diode <NUM> are arranged on the main body portion <NUM> of the lead-out structure <NUM>. The second connecting portion <NUM> is arranged close to the first edge <NUM> of the main body portion <NUM> in the length direction of the main body portion <NUM>. The distance between the second connecting portion <NUM> and the first edge <NUM> ranges from <NUM> to <NUM>. In the embodiments of the present application, the first connecting portion <NUM> and the second connecting portion <NUM> are arranged on the lead-out structure <NUM>, where the first connecting portion <NUM> is arranged in parallel to the main body portion <NUM>, and the second connecting portion <NUM> extends out of the first connecting portion <NUM> to be connected to the diode <NUM>. In addition, there is a distance between the second connecting portion <NUM> and the edge of the main body portion <NUM> of the lead-out structure <NUM> of the embodiment of the present application, so that there is a distance between two second connecting portions <NUM> respectively connected to two ends of the diode <NUM>, so as to avoid the risk of short circuit between cell strings <NUM>, thereby ensuring the reliability of the photovoltaic module and reducing the difficulty of preparing the photovoltaic module.

Claim 1:
A photovoltaic module, comprising:
at least one cell unit group (<NUM>), wherein the at least one cell unit group (<NUM>) comprises a plurality of cell strings (<NUM>) connected in series and/or in parallel, and adjacent cell strings (<NUM>) in the plurality of cell strings (<NUM>) are connected by a connection structure;
wherein the connection structure comprises a lead-out structure (<NUM>), and the lead-out structure (<NUM>) comprises a main body portion (<NUM>), a first connecting portion (<NUM>) and a second connecting portion (<NUM>) that are arranged on the main body portion (<NUM>); the first connecting portion (<NUM>) is connected to the second connecting portion (<NUM>), the first connecting portion (<NUM>) is disposed in parallel to a length direction of the main body portion (<NUM>), and the second connecting portion (<NUM>) extends out of the first connecting portion (<NUM>);
the main body portion (<NUM>) has a first edge (<NUM>) in the length direction of the main body portion (<NUM>), and the first connecting portion (<NUM>) is closer to the first edge (<NUM>) than the second connecting portion (<NUM>).