Back-contact cell, solar cell structure and solar cell module

Abstract

This application discloses a back-contact battery, solar cell structure, and solar cell module, which relate to the technical field of solar cells and are used to suppress current mismatches between different bus electrodes on a positive electrode and different bus electrodes on a negative electrode. The back-contact battery includes a battery body and a positive electrode and a negative electrode formed on a non-light-receiving surface of the battery body. Each of the positive electrode and the negative electrode includes a plurality of current collecting electrodes, a plurality of bus electrodes, and at least one connection electrode. At least one current collecting electrode included in the positive electrode and at least one current collecting electrode included in the negative electrode are both continuous current collecting electrodes. Each bus electrode includes a plurality of bus electrode segments spaced apart in a second direction, and two adjacent bus electrode segments on the same bus electrode are separated by a space from each collecting electrode of the opposite polarity. Each connection electrode is connected to all collecting electrodes of the same polarity as itself and is insulated from each collecting electrode of the opposite polarity.

Description

[Technical Field]

[0001] This application relates to the technical field of solar cells, and in particular to back-contact cells, solar cell structures and solar cell modules.

[0002] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims priority to a Chinese patent application filed with the China Patent Office on November 7, 2022, bearing application number 202222957031.9 and entitled "Back-contact battery, solar cell structure and solar cell module," the entire contents of which are incorporated herein by reference. [Background technology]

[0003] A back-contact cell is a solar cell in which both the emitter and the metal contact are on the back side of the cell, and the front side is not shielded by a metal electrode. Back-contact cells have higher short-circuit current and photoelectric conversion efficiency than solar cells with shielded front sides, and are currently one of the technological trends for realizing high-efficiency crystalline silicon cells.

[0004] However, current mismatch exists between different bus electrodes in the positive electrode and between different bus electrodes in the negative electrode included in conventional back-contact batteries, which is detrimental to improving the electrical performance of the back-contact batteries. Summary of the Invention

[0005] The present application aims to provide a back-contact battery, a solar cell structure, and a solar cell module that are used to suppress current mismatches that exist between different bus electrodes in a positive electrode and between different bus electrodes in a negative electrode included in a back-contact battery, and that are advantageous in improving the electrical performance of the back-contact battery.

[0006] In a first aspect, the present application provides a back-contact battery comprising a battery body and a positive electrode and a negative electrode formed on a non-light-receiving surface of the battery body, each of which includes a plurality of current collecting electrodes, a plurality of bus electrodes, and at least one connecting electrode.

[0007] The current collecting electrodes included in the positive electrode and the negative electrode both extend in a first direction and are arranged at alternating intervals in a second direction. The first direction is different from the second direction. At least one current collecting electrode included in the positive electrode and at least one current collecting electrode included in the negative electrode are both continuous current collecting electrodes. The bus electrodes included in the positive electrode and the negative electrode both extend in the second direction and are arranged at alternating intervals in the first direction. Each bus electrode is connected to a current collecting electrode of the same polarity as itself, and each bus electrode includes multiple bus electrode segments distributed at intervals in the second direction, and two adjacent bus electrode segments in the same bus electrode are separated by an interval from each collecting electrode of the opposite polarity. Each connection electrode is located outside all bus electrodes included in the positive electrode and negative electrode in the first direction. Each connection electrode is connected to all collecting electrodes of the same polarity as itself and is insulated from collecting electrodes of the opposite polarity.

[0008] In the back-contact battery provided by the present application, when the above technical solution is adopted, each bus electrode includes a plurality of bus electrode segments spaced apart in the second direction, and two adjacent bus electrode segments of the same bus electrode are spaced apart from each other by a gap from the current collecting electrode of the opposite polarity to the bus electrode. In this case, even if no insulating material is disposed between each bus electrode and the current collecting electrode of the opposite polarity to the bus electrode, no short circuit problem occurs, thereby reducing the amount of insulating material used and the manufacturing cost of the back-contact battery.

[0009] Furthermore, different bus electrode segments included in each bus electrode are connected to corresponding collecting electrodes of the same polarity, thereby concentrating carriers collected at corresponding positions on the collecting electrodes. Furthermore, if at least one collecting electrode included in the positive electrode is a continuous collecting electrode, the continuous collecting electrode included in the positive electrode connects bus electrode segments belonging to different bus electrodes in the positive electrode, thereby making the currents of the different bus electrode segments connected via the continuous collecting electrode the same. Next, the connecting electrode included in the positive electrode is connected to all collecting electrodes included in the positive electrode, and by connecting the collecting electrodes included in the positive electrode, it further connects the different bus electrode segments connected to the collecting electrodes included in the positive electrode. This is advantageous for further suppressing current mismatch between different bus electrodes included in the positive electrode, connecting all bus electrode segments belonging to the same bus electrode via the connecting electrode to prevent some bus electrode segments included in one bus electrode from becoming unable to connect to the intra-string interconnection member due to bias of the intra-string interconnection member welded to that bus electrode included in the positive electrode, allowing all carriers collected by each bus electrode segment included in the bus electrode to be extracted via the intra-string interconnection member, and further improving the photoelectric conversion efficiency of back-contact batteries. Similarly, the negative electrode in this application also has the beneficial effects of the positive electrode described above, and a detailed description thereof will be omitted here.

[0010] In one possible embodiment, the distance between two adjacent bus electrode segments on the same bus electrode in the second direction is 0.4 mm to 2 mm. In this case, the distance between two adjacent bus electrode segments on the same bus electrode in the second direction is appropriate. The small distance prevents a bus electrode segment from being connected to a current collecting electrode of the opposite polarity, which could cause a short circuit, and ensures that each bus electrode segment is separated from the current collecting electrode of the opposite polarity by the distance. Furthermore, the large distance reduces the length of each bus electrode segment in the second direction, which prevents carriers generated by photon absorption at the corresponding position of the battery body from concentrating in the bus electrode segment. This ensures that each bus electrode segment has a high carrier concentration capability, thereby further improving the electrical performance of the back-contact battery.

[0011] In one possible embodiment, each of the connection electrodes is located at an end in the first direction of all of the current collecting electrodes included in the positive and negative electrodes. In this case, each of the connection electrodes may be located at an edge in the first direction of the battery body, which increases the distance between each of the connection electrodes and the bus electrode of the opposite polarity to the connection electrode, and is advantageous in preventing short circuits.

[0012] In one possible implementation, all of the current collecting electrodes included in the positive electrode and the negative electrode have both ends in the same plane in the first direction. In this case, all of the current collecting electrodes included in the positive electrode and the negative electrode can be regularly distributed on the non-light-receiving surface of the electrode body in the first direction, which is advantageous for carriers generated by photon absorption in each part of the battery body in the first direction to be effectively collected by each current collecting electrode, and is further advantageous for improving the electrical performance of the back-contact battery.

[0013] In one possible embodiment, at least one connection electrode included in the positive electrode is located on a first outer side in the first direction of all bus electrodes included in the positive electrode and negative electrode, and at least one connection electrode included in the negative electrode is located on a second outer side in the first direction of all bus electrodes included in the positive electrode and negative electrode, with the second outer side and the first outer side being arranged opposite to each other.

[0014] When the above technical solution is adopted, all of the connection electrodes included in the positive electrode are similarly located on the first outer side in the first direction of all of the bus electrodes included in the back-contact battery. Similarly, all of the connection electrodes included in the negative electrode are similarly located on the second outer side in the first direction of all of the bus electrodes included in the back-contact battery. Furthermore, since the first outer side and the second outer side are arranged opposite to each other, it is possible to prevent short-circuit problems that may occur when connection electrodes with opposite polarities are located on the same outer side, and ensure stable electrical performance of the back-contact battery.

[0015] In one possible implementation, each of the current collecting electrodes has a gap extending in the first direction from the connecting electrode of the opposite polarity to itself, and in this case, each of the current collecting electrodes can be separated from the connecting electrode of the opposite polarity by the gap extending in the first direction, so that even if no insulating material is disposed between each of the current collecting electrodes and the connecting electrode of the opposite polarity to itself, no short circuit problem occurs, and therefore the amount of insulating material used can be further reduced, thereby reducing the manufacturing cost of the back-contact battery.

[0016] In one possible implementation, the multiple bus electrode segments included in the same bus electrode are distributed at equal intervals in the second direction. This is advantageous for uniformly distributing the multiple bus electrodes included in each of the positive and negative electrodes on the non-light-receiving surface of the cell body, and further for making the distance between each portion parallel to the non-light-receiving surface of the cell body and the corresponding bus electrode approximately equal. This is advantageous for carriers generated by photon absorption in each portion of the cell body to be collected in the corresponding current collecting electrode and concentrated in the corresponding bus electrode in a timely manner, thereby reducing the carrier recombination rate and further improving the photoelectric conversion efficiency of the back-contact cell.

[0017] In one possible implementation, the different bus electrode segments included in the same bus electrode have the same length, and the length directions of the bus electrode segments are parallel to the second direction. For the beneficial effect in this case, refer to the analysis of the beneficial effect obtained by distributing multiple bus electrode segments included in the same bus electrode at equal intervals in the second direction described above, and a detailed description thereof will be omitted here.

[0018] In one possible implementation, the bus electrodes of different polarities have the same number of bus electrode segments. In this case, the beneficial effect may be explained by the analysis of the beneficial effect of the plurality of bus electrode segments included in the same bus electrode being equally spaced in the second direction, and a detailed explanation thereof will be omitted here.

[0019] In one possible implementation, bus electrode segments in the same order in different bus electrodes of the same polarity have their ends in the same plane in the same direction, and bus electrode segments in different orders in the same bus electrode are spaced apart in the second direction.

[0020] When the above technical solution is adopted, bus electrode segments in the same order in different bus electrodes of the same polarity have both ends in the same plane in the same direction, so that the gaps between segments in the same order in different bus electrodes of the same polarity can extend along that direction, which is advantageous for the current collecting electrodes to be linear current collecting electrodes extending in a single linear direction and for simplifying the structure of the current collecting electrodes included in the positive and negative electrodes.

[0021] In one possible implementation, bus electrode segments of the same order in different bus electrodes of opposite polarity are arranged end-to-end in the second direction, and bus electrode segments of different orders in the same bus electrode are distributed at intervals in the second direction.

[0022] When the above technical solution is adopted, the heights in the second direction of bus electrode segments in the same order in different bus electrodes of opposite polarity are different. Based on this, and other factors being the same, the ends of bus electrode segments in the same order in different bus electrodes of opposite polarity are alternately arranged in the second direction, which can increase the distance between two adjacent bus electrode segments in the same bus electrode, further preventing short circuits caused by the connection between each bus electrode segment and the current collecting electrode of the opposite polarity to itself, and improving the electrical stability of the back-contact battery.

[0023] In one possible implementation, the back-contact cell further includes welds, each weld connected to a corresponding bus electrode.

[0024] In one possible implementation, among all welds included in a back-contact battery, welds located between two adjacent bus electrode segments, at least a portion of which is included in the same bus electrode, are type 1 welds, and the remaining welds are type 2 welds. Among all current collecting electrodes included in the positive and negative electrodes, those with at least a portion at the same height as the type 1 welds in the second direction are type 1 collecting electrodes, and the remaining current collecting electrodes are type 2 collecting electrodes. Each bus electrode has the same polarity as the welds provided thereon. Each type 1 collecting electrode includes multiple current collecting electrode segments distributed at intervals in the first direction, and two adjacent current collecting electrode segments included in the same type 1 collecting electrode are separated by an interval from the type 1 welds of the opposite polarity to the current collecting electrode segment itself. In this case, even if no insulating material is disposed between each type 1 collecting electrode and the welds of the opposite polarity to the current collecting electrode segment itself, short-circuit problems do not occur, further reducing the amount of insulating material used and reducing the manufacturing costs of back-contact batteries.

[0025] In a second aspect, the present application further provides a solar cell structure, the solar cell structure including an insulating material and a back-contact cell provided by the first aspect and its various implementations, the insulating material covering at least a space between two adjacent bus electrode segments included in each bus electrode.

[0026] In one possible implementation, the width of the insulating material in the first direction is greater than the width of the bus electrode but less than a predetermined width. The predetermined width is 1.5 mm to 10 mm. In this case, the width of the insulating material in the first direction is appropriate, and the increased width of the insulating material prevents an increase in the amount of insulating material used, which is advantageous for reducing the manufacturing cost of back-contact batteries. Furthermore, the narrow width of the insulating material prevents strict requirements for the placement position of the interconnecting members within the string when connecting different back-contact batteries, which is advantageous for reducing the difficulty of welding when connecting at least two back-contact batteries.

[0027] In one possible implementation, when the back-contact cells include welds, each weld connected to a corresponding bus electrode, the solar cell structure further includes a conductive adhesive, the conductive adhesive being applied to at least one of the welds.

[0028] When the above technical solution is adopted, within a certain range, the greater the thickness of the insulating material, the higher the insulating effect of the insulating material. When the insulating material is relatively thick, the top height of the insulating material may be greater than the top height of the welds. Based on this, by providing a conductive adhesive at each weld, the top height of the structure consisting of the conductive adhesive and the welds is equal to or greater than the top height of the insulating material, ensuring that the intra-string interconnecting members can be connected to the corresponding welds.

[0029] In a third aspect, the present application further provides a solar cell module, the solar cell module including a back-contact cell provided by the first aspect and its various implementations, or a solar cell structure provided by the second aspect and its various implementations.

[0030] The beneficial effects of the second and third aspects and their various implementation forms in the present application may refer to the analysis of the beneficial effects of the first aspect and its various implementation forms, and detailed description thereof will be omitted here.

[0031] The above has roughly described the technical solution of the present invention. In order to make the technical solution of the present invention more clearly understood and implemented according to the content of the specification, and to make the above and other objectives, features and advantages of the present invention more comprehensible, specific embodiments of the present invention are given below. [Brief explanation of the drawings]

[0032] In order to more clearly describe the embodiments of the present invention or the technical solutions in the prior art, the following will briefly describe the drawings necessary for describing the embodiments or the prior art. Of course, the drawings described below are part of the embodiments of the present invention, and those skilled in the art can come up with other drawings based on these drawings without any creative efforts. [Figure 1] 1 is a schematic diagram of the positive and negative electrodes of a conventional back-contact battery; FIG. [Figure 2] (1) and (2) are schematic diagrams of two types of structures of the battery body provided by the examples of the present application. [Figure 3] FIG. 1 is a schematic diagram of a first type of structure of a back-contact battery provided by an embodiment of the present application. [Figure 4] FIG. 2 is a schematic diagram of a second type of structure of a back-contact battery provided by an embodiment of the present application. [Figure 5] FIG. 1 is a schematic diagram of a third type of structure of a back-contact battery provided by an embodiment of the present application. [Figure 6] 1(1) is an enlarged view of the positional relationship between the collecting electrodes and bus electrodes in an example of the present application when the heights in the second direction of bus electrode segments in the same order in bus electrodes with different opposite polarities are partially the same, and FIG. 1(2) is an enlarged view of the positional relationship between the collecting electrodes and bus electrodes in an example of the present application when bus electrode segments in the same order in bus electrodes with different opposite polarities are arranged alternately in the second direction. [Figure 7] FIG. 1 is a schematic diagram of a fourth type of structure of a back-contact battery provided by an embodiment of the present application. [Figure 8] FIG. 1 is a schematic diagram of a fifth type of structure of a back-contact battery provided by an embodiment of the present application. [Figure 9] 1 is a schematic diagram of a solar cell structure provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0033] In order to clarify the objectives, technical solutions and advantages of the embodiments of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and are not all of the embodiments. Based on the embodiments of the present invention, all other embodiments that can be obtained by those skilled in the art without any creative efforts fall within the scope of protection of the present invention.

[0034] In order to make the technical problems, technical solutions and beneficial effects of the present application clearer and easier to understand, the present application will be described in more detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only for the purpose of interpreting the present application and are not intended to limit the present application.

[0035] When an element is referred to as being "fixed to" or "mounted on" another element, it should be understood that it may be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or indirectly connected to the other element.

[0036] It should be noted that the terms "first" and "second" are for descriptive purposes only and should not be understood to express or imply relative importance or the number of technical features being described. Thus, a feature qualified as "first" or "second" may expressly or imply the inclusion of one or more of that feature. In the description of this application, unless expressly and specifically limited, "plurality" means two or more than two. Unless expressly and specifically limited, "some" means one or more than one.

[0037] In the description of this application, it should be understood that orientations or positional relationships indicated by terms such as "upper," "lower," "front," "rear," "left," "right," etc. are based on the drawings and are intended merely to facilitate explanation and simplify the description of this application, and should not be construed as limiting this application, as they do not expressly or imply that the devices or elements described necessarily have a particular orientation or are constructed or operated in a particular orientation.

[0038] In the description of this application, unless otherwise clearly defined or limited, the terms "attach," "couple," and "connect" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, integral connection, mechanical connection, electrical connection, direct connection, indirect connection via an intermediate medium, internal communication between two elements, or an interaction between two elements. Those skilled in the art may understand the specific meaning of the above terms in this application depending on the specific situation.

[0039] Currently, solar cells are widely used as a new alternative form of energy. Here, a solar cell is a device that converts solar light energy into electrical energy. Specifically, a solar cell uses the principle of photovoltaic power to generate carriers, and then extracts the carriers using electrodes, which is advantageous for efficient use of electrical energy.

[0040] When both the positive and negative electrodes of a solar cell are located on the back surface of the solar cell, the solar cell is called a back-contact cell. Conventional back-contact cells include metal wrap-through (MWT) cells and interdigitated back contact (IBC) cells. The most notable feature of IBC cells is that both the emitter and metal contact are located on the back surface of the cell, eliminating the shielding effect of metal electrodes on the front surface, resulting in a higher short-circuit current (Isc). Furthermore, the back surface of IBC cells allows for wide metal grid lines to reduce series resistance (Rs), thereby improving the fill factor (FF). Furthermore, such unshielded cells not only have high conversion efficiency but also a more aesthetically pleasing appearance. Furthermore, because full back electrode assemblies are easier to assemble, IBC cells are currently one of the technological directions for achieving high-efficiency crystalline silicon batteries.

[0041] In an actual manufacturing process, as shown in FIG. 1 , both the positive electrode 2 and the negative electrode 3 included in the IBC battery are formed on the non-light-receiving surface of the battery body 1. Each of the positive electrode 2 and the negative electrode 3 includes a plurality of current collecting electrodes 4 and a plurality of bus electrodes 5. The plurality of current collecting electrodes 4 included in the positive electrode 2 and the negative electrode 3 extend in a first direction and are arranged at alternating intervals in a second direction. The plurality of bus electrodes 5 included in the positive electrode 2 and the negative electrode 3 extend in a second direction and are arranged at alternating intervals in the first direction, where the first direction is different from the second direction. Each current collecting electrode 4 is connected to a bus electrode 5 of the same polarity as itself, and each current collecting electrode 4 includes a plurality of current collecting electrode segments 13 arranged at intervals in the first direction. Adjacent two current collecting electrode segments 13 included in the same current collecting electrode 4 are separated by an interval from each bus electrode 5 of the opposite polarity to itself, preventing short-circuiting of the back-contact battery due to the connection of the positive electrode and the negative electrode 3.

[0042] However, as shown in FIG. 1 , different current collecting electrode segments 13 included in the same current collecting electrode 4 are insulated from each other, and each current collecting electrode segment 13 is used to collect carriers generated at a corresponding location on the battery body 1. Also, different current collecting electrode segments 13 are connected to different bus electrodes 5 included in the positive electrode 2, and different current collecting electrode segments 13 are connected to different bus electrodes 5 included in the corresponding negative electrode 3. Based on this, when a back-contact battery is in operation, the concentrations of carriers generated at different locations on the battery body 1 may differ, which may result in different currents collected by each current collecting electrode segment 13. Furthermore, the currents concentrated at different bus electrodes 5 included in the positive electrode 2 connected to different current collecting electrode segments 13 are also different. This means that there is a current mismatch problem between the different bus electrodes 5 included in the positive electrode 2. Similarly, there is a current mismatch problem between the different bus electrodes 5 included in the negative electrode 3, which is detrimental to improving the electrical performance of a back-contact battery.

[0043] To solve the above technical problems, in a first aspect, an embodiment of the present application provides a back-contact battery. As shown in Figures 3 to 5, the back-contact battery includes a battery body 1 and a positive electrode 2 and a negative electrode 3 formed on the non-light-receiving surface of the battery body 1. Each of the positive electrode 2 and the negative electrode 3 includes a plurality of current collecting electrodes 4, a plurality of bus electrodes 5, and at least one connecting electrode 6.

[0044] As shown in FIGS. 3 to 5 , the current collecting electrodes 4 included in the positive electrode 2 and the negative electrode 3 each extend in a first direction and are arranged at alternating intervals in a second direction. The first direction is different from the second direction. At least one current collecting electrode 4 included in the positive electrode 2 and at least one current collecting electrode 4 included in the negative electrode 3 are continuous current collecting electrodes. The bus electrodes 5 included in the positive electrode 2 and the bus electrodes 5 included in the negative electrode 3 each extend in the second direction and are arranged at alternating intervals in the first direction. Each bus electrode 5 is connected to a current collecting electrode 4 of the same polarity as itself, and each bus electrode 5 includes multiple bus electrode segments 7 distributed at intervals in the second direction, and two adjacent bus electrode segments 7 on the same bus electrode 5 are separated by an interval from each collecting electrode 4 of the opposite polarity. Each connection electrode 6 is located outside all of the bus electrodes 5 included in the positive electrode 2 and the negative electrode 3 in the first direction. Each connection electrode 6 is connected to all the current collecting electrodes 4 of the same polarity as itself, and is insulated from the current collecting electrodes 4 of the opposite polarity to itself.

[0045] Specifically, the specific structure and materials of the battery body can be set according to actual application scenarios and are not specifically limited herein. For example, the battery body may include a semiconductor substrate, a P-type doped semiconductor layer, and an N-type doped semiconductor layer. Here, the semiconductor substrate may be made of a semiconductor material such as silicon, germanium silicon, or gallium arsenide. The semiconductor substrate has opposing first and second surfaces. The second surface corresponds to the non-light-receiving surface of the battery body. The second surface has first and second regions parallel to the second surface, alternately arranged in the first direction. The longitudinal extension directions of the first and second regions are both parallel to the second direction. The P-type doped semiconductor layer is formed on or within the first region. The N-type doped semiconductor layer is formed on or within the second region. The doping concentrations of impurities in the P-type doped semiconductor layer and the N-type doped semiconductor layer can be set according to actual application scenarios as long as they are applicable to the back-contact battery provided by the embodiments of the present application.

[0046] 2(1), the battery body 1 may be a chamfered battery body, or as shown in FIG. 2(2), the battery body 1 may be a non-chamfered battery body.

[0047] As shown in FIGS. 3 to 5 , for the positive and negative electrodes, the collecting electrode 4 formed on the corresponding P-type doped semiconductor layer is the collecting electrode 4 included in the positive electrode 2 and is used to collect holes transferred from the P-type doped semiconductor layer. The bus electrode 5 connected to the collecting electrode 4 included in the positive electrode 2 is the bus electrode 5 included in the positive electrode 2. Conversely, the collecting electrode 4 formed on the corresponding N-type doped semiconductor layer is the collecting electrode 4 included in the negative electrode 3 and is used to collect electrons transferred from the N-type doped semiconductor layer. The bus electrode 5 connected to the collecting electrode 4 included in the negative electrode 3 is the bus electrode 5 included in the negative electrode 3.

[0048] As can be understood, one collecting electrode included in the positive electrode has an opposite polarity to one collecting electrode included in the negative electrode (or one bus electrode or one connection electrode included in the negative electrode) and has the same polarity as another collecting electrode included in the positive electrode (or one bus electrode or one connection electrode included in the positive electrode). Similarly, one bus electrode included in the positive electrode has an opposite polarity to one collecting electrode included in the negative electrode (or one bus electrode or one connection electrode included in the negative electrode) and has the same polarity as another bus electrode included in the positive electrode (or one collecting electrode or one connection electrode included in the positive electrode). One connection electrode included in the positive electrode has an opposite polarity to one collecting electrode included in the negative electrode (or one bus electrode or one connection electrode included in the negative electrode) and has the same polarity as one bus electrode included in the positive electrode (or one collecting electrode or another connection electrode included in the positive electrode). Accordingly, the situation of electrodes of the same polarity or opposite polarity corresponding to the collecting electrodes, bus electrodes, and connection electrodes included in the negative electrode may refer to the preceding paragraph, and a detailed description thereof will be omitted here.

[0049] Furthermore, the number and specifications of the current collecting electrodes included in each of the positive and negative electrodes, as well as the size of the gap in the second direction between the current collecting electrode included in the positive electrode and the current collecting electrode included in the adjacent negative electrode, can be set according to the actual application scenario, as long as they are applicable to the back-contact battery provided by the embodiments of the present application. Specifically, the number of current collecting electrodes included in each of the positive and negative electrodes may be the same or different. The gap in the second direction between the current collecting electrode included in the positive electrode and the current collecting electrode included in the adjacent negative electrode may be 1 mm to 2 mm. Of course, the gap may be set to other appropriate values ​​depending on the requirements of the actual application scenario. Next, as shown in Figures 3 to 5, all of the current collecting electrodes 4 included in the positive electrode 2 and the negative electrode 3 may be continuous current collecting electrodes. These continuous current collecting electrodes are uninterrupted current collecting electrodes. Alternatively, as shown in Figures 7 and 8, in both the positive electrode 2 and the negative electrode 3, some of the current collecting electrodes 4 are continuous current collecting electrodes, and the remaining current collecting electrodes 4 are discontinuous current collecting electrodes. In this case, the number of continuous and discontinuous current collecting electrodes in the positive electrode 2 and the negative electrode 3, as well as the number and interruption locations of the discontinuous current collecting electrodes, can be set according to the actual application scenario, as long as they are applicable to the back-contact battery provided by the embodiments of the present application.

[0050] The number and specifications of bus electrodes included in each of the positive and negative electrodes, and the size of the gap in the first direction between the bus electrode included in the positive electrode and the bus electrode included in the adjacent negative electrode, can be set according to the actual application scenario, as long as they are applicable to the back-contact battery provided by the embodiments of the present application. For example, the total number of bus electrodes included in the positive and negative electrodes may be 6 to 24. In actual applications, the number of bus electrodes included in the positive and negative electrodes may be the same or different.

[0051] The collecting electrodes included in the positive and negative electrodes described above may be straight collecting electrodes, wavy collecting electrodes, or bent-line collecting electrodes, etc. The specific shapes of the collecting electrodes included in the positive and negative electrodes can be set depending on the actual application scene and are not specifically limited here. Furthermore, the bus electrodes included in the positive and negative electrodes may be straight bus electrodes, wavy bus electrodes, or bent-line bus electrodes, etc. The specific shapes of the bus electrodes included in the positive and negative electrodes can be set depending on the actual application scene and are not specifically limited here.

[0052] 3 to 5, each bus electrode 5 includes a plurality of bus electrode segments 7 spaced apart in the second direction. Specifically, the plurality of bus electrode segments 7 included in the same bus electrode 5 may be arranged on the same plane in the first direction. Alternatively, at least one pair of bus electrode segments 7 in the same bus electrode 5 are spaced apart in the first direction. In actual application, the number of pairs of bus electrode segments 7 spaced apart in the first direction in the same bus electrode 5 can be set according to the actual application scenario, as long as it is applicable to the back-contact battery provided by the embodiments of the present application.

[0053] The first and second directions may be any two different directions parallel to the non-light-receiving surface. For example, as shown in Figures 3 to 5, when the cross section of the battery body 1 is rectangular, the first direction may be parallel to the long side of the rectangle, and the second direction may be parallel to the short side of the rectangle. In this case, the first direction is perpendicular to the second direction.

[0054] The size of the gap in the second direction between two adjacent bus electrode segments on the same bus electrode can be set according to actual needs and is not specifically limited herein. For example, the gap in the second direction between two adjacent bus electrode segments on the same bus electrode described above may be 0.4 mm to 2 mm. For example, the gap may be 0.4 mm, 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, or 2 mm. In this case, the size of the gap in the second direction between two adjacent bus electrode segments on the same bus electrode is appropriate, preventing a short circuit problem caused by a small gap between a bus electrode segment and a collecting electrode of the opposite polarity to itself, and ensuring that each bus electrode segment is spaced apart from a collecting electrode of the opposite polarity to itself by the gap. In addition, the large spacing reduces the length of each bus electrode segment in the second direction, preventing carriers generated by photon absorption at the corresponding position of the battery body from concentrating in the bus electrode segments. This ensures that each bus electrode segment has high carrier concentration capability, thereby further improving the electrical performance of the back-contact battery.

[0055] Regarding the above-mentioned connection electrodes, all of the connection electrodes included in each of the positive and negative electrodes are continuous connection electrodes. Continuous connection electrodes are uninterrupted connection electrodes. Furthermore, in the embodiments of the present application, the width of each connection electrode included in each of the positive and negative electrodes is not limited. For example, the width of the connection electrode may be the same as the width of the bus electrode or the width of the current collecting electrode. The number of connection electrodes included in each of the positive and negative electrodes may be one or more. Here, the number of connection electrodes included in the positive electrode may be the same as or different from the number of connection electrodes included in the negative electrode. The specific formation position of each connection electrode on the non-light-receiving surface of the battery body can be determined according to actual needs, as long as it can be ensured that each connection electrode is located outside all of the bus electrodes included in the positive and negative electrodes in the first direction. Here, as shown in FIG. 3 , the connection electrode 6 included in the positive electrode 2 and the connection electrode 6 included in the negative electrode 3 may be located on the same outside in the first direction as all of the bus electrodes 5. In this case, the connection electrode 6 can be separated from the current collecting electrode 4 of the opposite polarity via an insulating material. Of course, mutual insulation between the two electrodes may be achieved by other means. Alternatively, as shown in Figures 4 and 5, at least one connection electrode 6 included in the positive electrode 2 is located on a first outer side in the first direction of all of the bus electrodes 5 included in the positive electrode 2 and the negative electrode 3. At least one connection electrode 6 included in the negative electrode 3 is located on a second outer side in the first direction of all of the bus electrodes 5 included in the positive electrode 2 and the negative electrode 3. The second outer side and the first outer side are arranged opposite to each other. In this case, it is possible to prevent a short circuit problem that would occur if connection electrodes 6 with opposite polarities were located on the same outer side, and it is possible to ensure stable electrical performance of the back-contact battery.

[0056] 3 to 5, in the back-contact battery provided by the embodiment of the present application, each bus electrode 5 includes a plurality of bus electrode segments 7 spaced apart in the second direction, and two adjacent bus electrode segments 7 on the same bus electrode 5 are spaced apart from each current collecting electrode 4 of the opposite polarity. In this case, even if no insulating material is disposed between each bus electrode 5 and the current collecting electrode 4 of the opposite polarity, no short circuit problem occurs. This reduces the amount of insulating material used and the manufacturing cost of the back-contact battery.

[0057] 3 to 5 , different bus electrode segments 7 included in each bus electrode 5 are connected to corresponding collecting electrodes 4 of the same polarity, thereby concentrating carriers collected at corresponding positions on the collecting electrodes 4. Furthermore, if at least one collecting electrode 4 included in the positive electrode 2 is a continuous collecting electrode, the continuous collecting electrode included in the positive electrode 2 connects bus electrode segments 7 belonging to different bus electrodes 5 in the positive electrode 2, thereby making the currents of the different bus electrode segments 7 connected via the continuous collecting electrode the same. Next, the connecting electrode 6 included in the positive electrode 2 is connected to all of the collecting electrodes 4 included in the positive electrode 2, and by connecting the collecting electrodes 4 included in the positive electrode 2, further connects the different bus electrode segments 7 connected to the collecting electrodes 4 included in the positive electrode 2. This is advantageous in further suppressing current mismatch between different bus electrodes 5 included in the positive electrode 2, connecting all bus electrode segments 7 belonging to the same bus electrode 5 via the connection electrode 6, and preventing some bus electrode segments 7 included in one bus electrode 5 from becoming unable to connect to the intra-string interconnection member due to bias of the intra-string interconnection member welded to that bus electrode 5 included in the positive electrode 2, and is advantageous in enabling all carriers collected by each bus electrode segment 7 included in the bus electrode 5 to be extracted via the intra-string interconnection member, and is also advantageous in improving the photoelectric conversion efficiency of the back-contact battery. Similarly, the negative electrode 3 in the examples of the present application also has the beneficial effects of the positive electrode 2 described above, and a detailed description thereof will be omitted here.

[0058] In some implementations, each successive current collecting electrode is connected to a bus electrode 5 with the same polarity as the successive current collecting electrode. For example, each successive current collecting electrode of the positive electrode 2 is connected to the bus electrode 5 of the positive electrode 2, and each successive current collecting electrode of the negative electrode 3 is connected to the bus electrode 5 of the negative electrode 3. In this way, not only is the current mismatch between different bus electrodes 5 reduced, but carriers collected by successive current collecting electrodes can be collected and transported by nearby bus electrodes 5, shortening the path for carrier transfer. As a result, transport resistance can be reduced, and the photoelectric conversion efficiency of back-contact cells can be improved.

[0059] In actual application, as shown in Figures 3 and 4, each connection electrode 6 may be located on a current collecting electrode 4 included in the positive electrode 2 and the negative electrode 3. Alternatively, as shown in Figure 5, each connection electrode 6 may be located at an end in the first direction of all current collecting electrodes 4 included in the positive electrode 2 and the negative electrode 3. In this case, each connection electrode 6 may be located at an edge position in the first direction of the battery body 1, thereby increasing the distance between each connection electrode 6 and the bus electrode 5 of the opposite polarity to itself, which is advantageous in preventing short circuits.

[0060] 3 and 4, all of the current collecting electrodes 4 included in the positive electrode 2 and the negative electrode 3 may be arranged so that both ends in the first direction are on the same plane. In this case, all of the current collecting electrodes 4 included in the positive electrode 2 and the negative electrode 3 can be regularly distributed on the non-light-receiving surface of the electrode body in the first direction, which is advantageous for carriers generated by photon absorption in each part of the battery body 1 in the first direction to be effectively collected by each current collecting electrode 4, and is also advantageous for improving the electrical performance of the back-contact battery.

[0061] Alternatively, the end of at least one current collecting electrode in the first direction may be arranged alternately with the end of the remaining current collecting electrodes in the first direction. In this case, as shown in Fig. 5, all current collecting electrodes 4 included in the positive electrode 2 may have both ends in the same plane in the first direction, and all current collecting electrodes 4 included in the negative electrode 3 may have both ends in the same plane in the first direction, and the ends of all current collecting electrodes 4 included in the positive electrode 2 may be arranged alternately with the ends of all current collecting electrodes 4 included in the negative electrode 3 in the first direction. In this case, it is advantageous that each connection electrode 6 is connected only to current collecting electrodes 4 of the same polarity as itself and is separated from current collecting electrodes 4 of the opposite polarity without an insulating material being disposed therebetween.

[0062] In one possible embodiment, each of the current collecting electrodes has a gap extending in the first direction from the connecting electrode 6 of the opposite polarity to itself. Here, as shown in Fig. 5, the gap may be the gap between the end of each current collecting electrode 4 in the first direction and the connecting electrode 6 of the opposite polarity to itself. Alternatively, the gap may be a gap provided on the current collecting electrode, and the gap is used to divide the current collecting electrode into at least two current collecting electrode segments.

[0063] Specifically, the size of the interval can be set according to actual needs, and is not specifically limited here.

[0064] When the above technical solution is adopted, as shown in FIG. 5 , each current collecting electrode 4 can be separated from the connecting electrode 6 of the opposite polarity by a gap extending in the first direction, so that even if no insulating material is disposed between each current collecting electrode 4 and the connecting electrode 6 of the opposite polarity, no short circuit problem will occur. This further reduces the amount of insulating material used and reduces the manufacturing cost of the back-contact battery.

[0065] In actual application, as described above, each bus electrode includes a plurality of bus electrode segments spaced apart in the second direction. Specifically, the number of bus electrode segments included in different bus electrodes of the same polarity may be the same or different. For example, as shown in FIGS. 3 to 5 , each bus electrode 5 included in the positive electrode 2 includes 10 bus electrode segments 7. Here, as shown in FIGS. 3 to 5 , if the number of bus electrode segments 7 included in different bus electrodes 5 of the same polarity is the same, the plurality of bus electrodes 5 included in each of the positive electrode 2 and the negative electrode 3 are advantageously uniformly distributed on the non-light-receiving surface of the battery body 1. Furthermore, the distance between each portion of the battery body 1 parallel to the non-light-receiving surface and the corresponding bus electrode 5 can be approximately equal. This advantageously allows carriers generated by photon absorption in each portion of the battery body 1 to be collected by the corresponding current collecting electrode 4 and concentrated on the corresponding bus electrode 5 in a timely manner. This reduces the carrier recombination rate and further improves the photoelectric conversion efficiency of the back-contact battery.

[0066] In terms of length, different bus electrode segments included in the same bus electrode may have the same or different lengths. Here, the length direction of the bus electrode segments is parallel to the second direction. For example, as shown in FIG. 3 , the bus electrode located in the first row is bus electrode 5 included in positive electrode 2, and different bus electrode segments 7 included in bus electrode 5 are arranged in order from top to bottom. Here, the first to tenth bus electrode segments included in bus electrode 5 have the same length in the second direction.

[0067] In addition, the lengths in the second direction of any two bus electrode segments belonging to different bus electrodes may be the same or different. Here, if the lengths of any two bus electrode segments belonging to different bus electrodes are the same, it is advantageous for all bus electrodes in the back-contact battery to be uniformly distributed on the non-light-receiving surface of the battery body, and it is advantageous for carriers generated by light absorption in the battery body to be extracted by the bus electrodes in a timely manner, thereby reducing the carrier recombination rate and further improving the electrical performance of the back-contact battery.

[0068] In terms of distribution, the intervals between any two pairs of bus electrode segments in the same bus electrode may be the same or different. Here, as shown in Figures 3 to 5, when the intervals between any two pairs of bus electrode segments 7 in the same bus electrode 5 are equal, the multiple bus electrode segments 7 included in the same bus electrode 5 are distributed at equal intervals in the second direction. For the beneficial effects in this case, refer to the analysis of the beneficial effects when the number of bus electrode segments 7 included in different bus electrodes 5 of the same polarity is the same, and a detailed description thereof will be omitted here.

[0069] Furthermore, bus electrode segments in the same order in different bus electrodes of the same polarity may be arranged alternately, or both ends may be on the same plane in the same direction. Bus electrode segments in different orders in the same bus electrode are distributed at intervals in the second direction. Here, as shown in Figures 3 to 5 , if bus electrode segments 7 in the same order in different bus electrodes 5 of the same polarity are on the same plane in the same direction, the intervals between the segments in the same order in different bus electrodes 5 of the same polarity can extend in that direction. This is advantageous for the current collecting electrodes 4 to be linear current collecting electrodes extending in a single linear direction, which is advantageous for simplifying the structure of the current collecting electrodes 4 included in the positive electrode 2 and the negative electrode 3.

[0070] As shown in FIG. 6(1), the heights of bus electrode segments 7 in the same order in bus electrodes 5 of different opposite polarities may partially overlap in the second direction. Bus electrode segments 7 in different orders in the same bus electrode 5 are distributed at intervals in the second direction. In this case, if other factors are the same, the heights of bus electrode segments 7 in the same order in bus electrodes 5 of different opposite polarities partially overlap in the second direction, which can increase the length of each bus electrode segment 7 and is therefore advantageous for improving the carrier concentration ability of each bus electrode segment 7. Alternatively, as shown in FIG. 6(2), the bus electrode segments 7 in the same order in the above-mentioned bus electrodes 5 of different opposite polarities may be arranged so that their ends are alternated in the second direction. Bus electrode segments 7 in different orders in the same bus electrode 5 are distributed at intervals in the second direction. In this case, the heights of bus electrode segments 7 in the same order in bus electrodes 5 of different opposite polarities in the second direction are different. On this basis, when other factors are the same, the bus electrode segments 7 of the same order in different bus electrodes 5 of opposite polarity are arranged with their ends alternately in the second direction, thereby increasing the distance between two adjacent bus electrode segments 7 included in the same bus electrode 5, thereby further preventing short circuits from occurring due to the connection between each bus electrode segment 7 and the current collecting electrode 4 of the opposite polarity to itself, and improving the electrical stability of the back-contact battery.

[0071] In one possible implementation, as shown in Figures 7 and 8, the back-contact battery further includes welds 8, each connected to a corresponding bus electrode 5, facilitating connection between the bus electrode 5 and a corresponding intra-string interconnect member.

[0072] Specifically, due to the number of bus electrodes, each bus electrode 5 may be connected to only one weld. Alternatively, as shown in Figures 7 and 8, each bus electrode 5 may be connected to multiple welds 8 spaced apart in the second direction. Here, when each bus electrode 5 is connected to only one weld 8, as opposed to connecting each bus electrode 5 to multiple welds 8 spaced apart in the second direction, problems such as solder fracture of the intra-string interconnection members due to reduced weld strength caused by welding the intra-string interconnection members to only one weld 8 can be prevented, and the welding quality during series welding of back-contact batteries provided by embodiments of the present application can be improved.

[0073] Furthermore, when each bus electrode is connected to a plurality of welds spaced apart in the second direction, the number of welds connected to different bus electrodes may be the same or different. Here, as shown in Figures 7 and 8, when the number of welds 8 connected to different bus electrodes 5 is the same, it is advantageous for the plurality of welds 8 included in the back-contact battery to be uniformly distributed above the battery body 1, and it is advantageous for a conventional series welding device to connect a plurality of back-contact batteries provided by the present embodiment in series via an intra-string interconnection member, thereby improving welding efficiency.

[0074] 7 and 8, multiple welds 8 connected to the same bus electrode 5 may be distributed at equal intervals, which is advantageous for improving the welding quality between the intra-string interconnection members and the corresponding bus electrodes 5.

[0075] In view of the shape, the cross-sectional shape of the weld connected to the bus electrode may be rectangular, circular, elliptical, or the like. The length of the weld in the first direction may be equal to or greater than the width of the bus electrode in the first direction, which is advantageous for improving the weld strength between the bus electrode and the corresponding intra-string interconnection member. For example, when the cross-sectional shape of the weld is rectangular, the long side of the rectangle may be 3 mm and the short side may be 2 mm.

[0076] In one example, as shown in FIGS. 7 and 8 , among all welds 8 included in a back-contact battery, those welds 8 at least partially located between two adjacent bus electrode segments 7 included in the same bus electrode 5 are type 1 welds 9, and the remaining welds 8 are type 2 welds 10. Among all current collecting electrodes 4 included in the positive electrode 2 and negative electrode 3, those current collecting electrodes 4 at least partially located at the same height as the type 1 welds 9 in the second direction are type 1 current collecting electrodes 11, and the remaining current collecting electrodes 4 are type 2 current collecting electrodes 12. Each bus electrode 5 has the same polarity as the welds 8 provided thereon. Each type 1 current collecting electrode 11 includes multiple current collecting electrode segments 13 distributed at intervals in the first direction, and two adjacent current collecting electrode segments 13 included in the same type 1 current collecting electrode 11 are separated by an interval from the type 1 welds 9 of the opposite polarity to the current collecting electrode segments 13 themselves.

[0077] Specifically, the number of type 1 welds and type 2 welds included in a back-contact battery can be set according to actual needs and is not specifically limited herein. For example, as shown in FIG. 7, each weld 8 included in a back-contact battery is a type 1 weld 9. Alternatively, some of the welds included in a back-contact battery are type 1 welds, and the remaining welds are type 2 welds. For example, as shown in FIG. 8, the number of columns in which welds 8 are located is sorted from right to left, and the welds 8 in the first column of back-contact batteries are type 1 welds 9, and the welds 8 in the remaining columns are type 2 welds 10. Alternatively, each weld included in a back-contact battery is a type 2 weld.

[0078] In addition, the number and length of the collecting electrode segments distributed at intervals in the first direction included in each of the first type collecting electrodes, and the interval between two adjacent collecting electrode segments included in the same first type collecting electrode, can be set according to the number of first type welds that are at the same height as at least a part of the first type collecting electrode in the second direction and have the opposite polarity to the first type collecting electrode itself, and actual needs, and are not specifically limited herein.

[0079] When the above technical solution is adopted, even if no insulating material is disposed between each first-class current collecting electrode and the opposite polarity weld, no short circuit problem occurs, so the amount of insulating material used can be reduced, and the manufacturing cost of the back-contact battery can be reduced.

[0080] In a second aspect, embodiments of the present application further provide a solar cell structure, as shown in Figure 9, which includes an insulating material 14 and a back-contact cell provided by the first aspect and its various implementations. The insulating material 14 covers at least the space between two adjacent bus electrode segments included in each bus electrode.

[0081] Specifically, the width of the insulating material can be set according to actual needs and is not specifically limited herein. For example, the width of the insulating material in the first direction may be greater than the width of the bus electrode but smaller than a predetermined width. The predetermined width may be 1.5 mm to 10 mm. In this case, the width of the insulating material in the first direction is appropriate, preventing an increase in the amount of insulating material used due to a large insulating material width, which is advantageous for reducing the manufacturing cost of back-contact batteries. Furthermore, a small insulating material width prevents strict requirements for the placement of intra-string interconnectors during the process of connecting different back-contact batteries, which is advantageous for reducing the difficulty of welding to connect at least two back-contact batteries.

[0082] In one possible implementation, as shown in FIG. 9 , when the back-contact cell includes welds 8 and each weld 8 is connected to a corresponding bus electrode, the solar cell structure further includes a conductive adhesive 15. The conductive adhesive 15 is provided on at least one weld 8. In this case, within a certain range, if the thickness of the insulating material 14 is large, the insulating effect of the insulating material 14 is enhanced. If the insulating material 14 is relatively thick, the top height of the insulating material 14 may be greater than the top height of the welds 8. Based on this, by providing the conductive adhesive 15 on each weld 8, the top height of the structure consisting of the conductive adhesive 15 and the welds 8 is equal to or greater than the top height of the insulating material 14, ensuring that the intra-string interconnect members can be connected to the corresponding welds 8. As can be seen from the above, the thickness of the conductive adhesive 15 can be determined according to the height difference between the welds 8 and the top of the insulating material 14 and is not specifically limited herein.

[0083] In a third aspect, embodiments of the present application further provide a solar cell module, the solar cell module including a back-contact cell provided by the first aspect and its various implementations, or a solar cell structure provided by the second aspect and its various implementations.

[0084] The beneficial effects of the second and third aspects and their various implementation forms in the embodiments of the present application may refer to the analysis of the beneficial effects of the first aspect and its various implementation forms, and detailed description thereof will be omitted here.

[0085] The above are only specific embodiments of the present application, and the scope of protection of the present application is not limited thereto. Any changes or replacements that can be easily thought of by a person skilled in the art within the technical scope described in the present application are included in the scope of protection of the present application. Therefore, the scope of protection of the present application shall be equivalent to the scope of protection of the claims.

[0086] The terms "one embodiment," "embodiment," or "one or more embodiments" used herein mean that a particular feature, structure, or characteristic described by the embodiment is included in at least one embodiment of the present invention. Note also that various instances of the phrase "in one embodiment" do not necessarily refer to the same embodiment.

[0087] In the specification provided herein, numerous specific details have been set forth. However, it will be understood that embodiments of the present invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this specification.

[0088] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not stated in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The terms first, second, third, etc. do not denote any order. These terms may also be interpreted as names.

[0089] Finally, it should be mentioned that the above embodiments are only for illustrating the technical solutions of the present invention, and are not intended to limit the same. Although the present invention has been described in detail with reference to the above embodiments, it is naturally understood by those skilled in the art that modifications to the technical solutions described in the above embodiments or equivalent substitutions for some technical features thereof are possible, and such modifications or substitutions do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention. [Explanation of symbols]

[0090] 1 Battery body 2 positive electrode 3 negative electrode 4 Current collector electrode 5 Bus electrode 6 Connecting electrodes 7 Bath electrode segments 8 Welds 9. Type 1 welds 10. Type 2 welds 11 Type 1 current collecting electrode 12. Type 2 collector electrodes 13 Collector electrode segment 14 Insulating materials 15 Conductive adhesive

Claims

1. A back-contact battery including a battery body and a positive electrode and a negative electrode formed on a non-light-receiving surface of the battery body, wherein the positive electrode and the negative electrode each include a plurality of current collecting electrodes, a plurality of bus electrodes, and at least one connecting electrode; the current collecting electrodes included in the positive electrode and the current collecting electrodes included in the negative electrode each extend in a first direction and are provided alternately at intervals in a second direction different from the first direction, and the at least one current collecting electrode included in the positive electrode and the at least one current collecting electrode included in the negative electrode are both continuous current collecting electrodes; the bus electrodes included in the positive electrode and the bus electrodes included in the negative electrode both extend in the second direction and are arranged alternately at intervals in the first direction, each bus electrode is connected to the collecting electrode of the same polarity as the bus electrode itself, each bus electrode includes a plurality of bus electrode segments distributed at intervals in the second direction, and two adjacent bus electrode segments in the same bus electrode are separated by an interval from each collecting electrode of the opposite polarity to the bus electrode itself, a back-contact battery in which each of the connection electrodes is located outside all of the bus electrodes included in the positive electrode and the negative electrode in the first direction, and each of the connection electrodes is connected to all of the current collecting electrodes of the same polarity as itself and is insulated from each of the current collecting electrodes of the opposite polarity to itself.

2. 2. The back-contact battery of claim 1, wherein the spacing in the second direction between two adjacent bus electrode segments of the same bus electrode is 0.4 mm to 2 mm.

3. Each of the connection electrodes is located at an end in the first direction of all of the current collecting electrodes included in the positive electrode and the negative electrode; and / or 2. The back-contact battery of claim 1, wherein all of the current collecting electrodes included in the positive electrode and the negative electrode have opposite ends in the first direction that are in the same plane.

4. the at least one connection electrode included in the positive electrode is located on a first outer side in the first direction of all the bus electrodes included in the positive electrode and the negative electrode; 2. The back-contact battery of claim 1, wherein the at least one connection electrode included in the negative electrode is located on a second outer side in the first direction of all of the bus electrodes included in the positive electrode and the negative electrode, and the second outer side and the first outer side are provided opposite to each other.

5. 5. The back-contact battery of claim 1, wherein each current collecting electrode has a spacing extending in the first direction relative to the connecting electrode of opposite polarity to the current collecting electrode.

6. The bus electrode segments included in the same bus electrode are distributed at equal intervals in the second direction, and / or 5. The back-contact battery of claim 1, wherein the different bus electrode segments included in the same bus electrode have the same length, and the length directions of the bus electrode segments are parallel to the second direction.

7. the different bus electrodes of the same polarity have the same number of bus electrode segments; and / or the bus electrode segments in the same order in different bus electrodes of the same polarity are coplanar in both ends in the same direction, and the bus electrode segments in different orders in the same bus electrode are spaced apart in the second direction; and / or 5. The back-contact battery of claim 1, wherein the bus electrode segments in the same order in the different bus electrodes of opposite polarity are arranged with their ends alternating in the second direction, and the bus electrode segments in different orders in the same bus electrode are distributed at intervals in the second direction.

8. The back-contact battery of claim 1 , further comprising welds, each weld connected to a corresponding bus electrode.

9. Among all the welds included in the back-contact battery, the welds at least partially located between two adjacent bus electrode segments included in the same bus electrode are type 1 welds, and the remaining welds are type 2 welds; Among all the current collecting electrodes included in the positive electrode and the negative electrode, the current collecting electrodes at least some of which are at the same height as the first type weld in the second direction are first type current collecting electrodes, and the remaining current collecting electrodes are second type current collecting electrodes; 9. The back-contact battery of claim 8, wherein each bus electrode has the same polarity as the weld provided thereon, each first-type current collecting electrode includes a plurality of current collecting electrode segments distributed at intervals in the first direction, and two adjacent current collecting electrode segments included in the same first-type current collecting electrode are separated by a space from the first-type weld of opposite polarity to the bus electrode.

10. an insulating material and the back contact battery of any one of claims 1 to 9; The insulating material covers at least a space between two adjacent bus electrode segments included in each of the bus electrodes.

11. a width of the insulating material in the first direction is greater than a width of the bus electrode and smaller than a predetermined width; The solar cell structure of claim 10, wherein the predetermined width is between 1.5 mm and 10 mm.

12. 12. The solar cell structure of claim 10 or 11, wherein when the back contact battery is the back contact battery of claim 8 or 9, the solar cell structure further includes a conductive adhesive provided at one of the welds.

13. A solar cell module comprising a back contact cell according to any one of claims 1 to 9 or a solar cell structure according to any one of claims 10 to 12.

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