CN220543923U - Cells and photovoltaic modules - Google Patents

Abstract

The embodiment of the disclosure relates to the field of photovoltaic cells, and provides a battery piece and a photovoltaic module, which comprises: a substrate; the passivation layer covers the surface of the substrate; the first grid lines are arranged in the first direction, each grid line group in the first direction comprises at least two first grid lines which are arranged at intervals in the first direction, and each first grid line in the at least two first grid lines extends in the first direction, is positioned in the passivation layer and penetrates through the passivation layer; each grid line group further comprises a plurality of shunt lines which are arranged at intervals along the first direction, each shunt line in the plurality of shunt lines extends along the second direction, the shunt lines are electrically contacted with at least two first grid lines in the grid line group, and at least part of the shunt lines are used for connecting welding strips. The battery piece and the photovoltaic module provided by the embodiment of the application are at least beneficial to improving the yield of the photovoltaic module.

Description

Cells and photovoltaic modules

Technical field

Embodiments of the present application relate to the field of photovoltaic cells, and in particular to a cell sheet and a photovoltaic module.

Background technique

Solar cells are devices that directly convert light energy into electrical energy through the photoelectric effect or photochemical effect. Single solar cells cannot directly generate electricity and be used as power source. To use as a power source, several single cells must be connected in series, parallel and tightly sealed with welding ribbons into components before use. Solar cell components (also called solar panels) are the core part of the solar power generation system and the most important part of the solar power generation system. The function of the solar cell module is to convert solar energy into electrical energy, or send it to the battery for storage, or drive the load.

Battery sheets are very fragile, and it is generally necessary to install adhesive films and covers on the upper and lower surfaces of the battery components to protect the battery sheets. The cover is generally made of photovoltaic glass. Photovoltaic glass cannot be directly attached to the cell, and an adhesive film is required to play a bonding role in the middle. The connection between battery cells usually requires a welding ribbon for collecting current. Conventional welding ribbons require alloying between the welding ribbon and the fine grid during welding. Cell efficiency and cell yield are usually improved by balancing the light shielding and conductivity between the main grid and the auxiliary grid, but there are still many factors that affect the yield of photovoltaic modules.

Utility model content

Embodiments of the present application provide a cell sheet and a photovoltaic module, which are at least beneficial to improving the yield rate of the photovoltaic module.

According to some embodiments of the present application, on the one hand, embodiments of the present application provide a battery sheet, including: a substrate; a passivation layer covering the surface of the substrate; a plurality of grid line groups arranged along the second direction, the plurality of grid lines Each grid line group in the group includes at least two first grid lines spaced apart along the second direction, each of the at least two first grid lines extends along the first direction, and the first grid line Located in the passivation layer and penetrating the passivation layer; each gate line group also includes a plurality of shunt lines arranged at intervals along the first direction, and each of the plurality of shunt lines extends along the second direction. , the shunt wire is in electrical contact with at least two first grid lines in the grid line group, and at least part of the shunt wire is used to connect the soldering strips.

In some embodiments, the shunt line is located on the surface of the passivation layer; alternatively, the shunt line is located in the passivation layer and penetrates the passivation layer, and the shunt line and the gate line are an integrally formed structure.

In some embodiments, along the second direction, the shunt lines in adjacent gate line groups are staggered, or the shunt lines in adjacent gate line groups are aligned.

In some embodiments, the number of first gate lines in the same gate line group is 3 to 6.

In some embodiments, the number of shunt lines in the same gate line group ranges from 5 to 20.

In some embodiments, the distance between adjacent shunt lines along the first direction ranges from 6 to 20 mm.

In some embodiments, the first grid line connected to the end of the shunt line includes: a first grid line body and a plurality of first thickened portions, and along the second direction, among the plurality of first thickened portions The width of each first thickened portion is greater than the width of the first grid line body, and the first thickened portion is used for connecting with the solder ribbon.

In some embodiments, the shunt line includes: a shunt line body and a plurality of widened portions; along the first direction, the width of each of the plurality of widened portions is greater than the width of the shunt line body , the widened part is used to connect with the welding strip.

In some embodiments, the method further includes: a plurality of second gate lines, each of the plurality of second gate lines extending along the first direction, and the second gate line is located in the passivation layer and runs through the passivation layer. layer, the second gate line is also located between adjacent gate line groups.

According to some embodiments of the present application, on the other hand, the embodiments of the present application also provide a photovoltaic module, including: a plurality of cell sheets as in any one of the above embodiments; a plurality of glue dots, the glue dots are located on the surface of the cell chip, On each cell sheet, along the second direction, each grid line group corresponds to a glue point, wherein, along the second direction, each glue point covers part of the surface of a shunt line, and/or, Each glue point covers part of the surface of a first grid line that is in electrical contact with the shunt line; a plurality of welding ribbons, each of the plurality of welding ribbons extends along the second direction, and the welding ribbons are used to connect adjacent On each battery sheet, the welding strip is fixed on the surface of the battery sheet through a plurality of glue dots arranged along the second direction.

The technical solution provided by the embodiment of the present application has at least the following advantages: The battery sheet 100 provided by the embodiment of the present application includes a substrate 101 and a passivation layer 102 covering the surface of the substrate 101. The passivation layer 102 can protect the battery sheet 100 against pollution from the external environment. and corrosion, and at the same time, the efficiency of the battery piece 100 can be improved. Each of the plurality of grid line groups 103 arranged along the second direction Y includes a plurality of first grid lines 113 extending along the first direction The carriers inside the battery piece 100 are extracted. The first grid line 113 in the grid line group 103 is connected through a plurality of shunt lines 104, and at least part of the shunt lines 104 are used to connect the solder ribbons, then the first grid line 113 in the grid line group 103 can be directly connected to the solder ribbons. Connect or connect with the solder ribbon through the shunt line 104 to improve the yield of the photovoltaic module.

Description of drawings

One or more embodiments are exemplified by the pictures in the corresponding drawings. These illustrative illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the drawings do not constitute a limitation on proportions; in order to To more clearly illustrate the technical solutions in the embodiments of the present application or traditional technologies, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. , for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without exerting creative efforts.

Figure 1 is a top view of a battery sheet provided by an embodiment of the present application;

Figure 2 is a schematic cross-sectional structural diagram along the AA1 direction in Figure 1;

Figure 3 is a schematic structural diagram of various gate line groups provided by an embodiment of the present application;

Figure 4 is a schematic cross-sectional structural diagram of the battery sheet in Figure 1 along the BB1 direction;

Figure 5 is a schematic diagram of another cross-sectional structure of the battery sheet in Figure 1 along the BB1 direction;

6 to 7 are top views of various battery sheets provided by an embodiment of the present application;

8 to 9 are partial enlarged structural schematic diagrams of various gate line groups provided by an embodiment of the present application;

Figure 10 is a top view of another battery sheet provided by an embodiment of the present application;

Figure 11 is a schematic cross-sectional structural diagram of the cell sheet in Figure 10 along the CC1 direction;

Figure 12 is a partially enlarged structural schematic diagram of yet another gate line group provided by an embodiment of the present application;

Figures 13 to 15 are partial schematic diagrams of various photovoltaic modules provided by another embodiment of the present application;

16 to 18 are partial enlarged structural diagrams of grid line groups in various photovoltaic modules provided by another embodiment of the present application.

Detailed ways

It can be known from the background art that the yield of photovoltaic modules needs to be improved.

The analysis found that in photovoltaic module technology, the main grid of the cell is usually welded to the welding ribbon. At the same time, the positive and negative electrodes of two adjacent cells are connected through the welding ribbon to form a battery string, and then the battery strings are arranged in a certain manner. The circuit is connected, and then encapsulated using packaging materials to form photovoltaic modules. The welding of the main grid and the welding strip usually uses a certain number of infrared lamps arranged to form a high-temperature area, so that the tin-lead alloy on the surface of the welding strip melts at high temperature, and the silver slurry of the welding strip and the main grid on the battery surface is fused. Together. However, the typical welding temperature is between 220 and 350°C, and the use of high-temperature welding processes can easily lead to stress warping of the cells, resulting in cracks or fragments. In addition, due to the influence of the wire diameter and yield strength of the welding ribbon, traditional welding methods There is a large stress between cells, and photovoltaic modules are prone to cracks when exposed to wind, snow and other weather conditions outdoors, resulting in reduced power generation and reduced reliability of photovoltaic modules.

In order to avoid the use of infrared welding, low melting point metal can be used as solder to make solder ribbons. The solder ribbons are first fixed on the surface of the cells through glue; then during the lamination process of photovoltaic modules, the temperature and temperature of the laminator are used. The pressure helps the low-melting solder ribbon bond to the grid lines. As a result, the grid lines on adjacent cells can be directly electrically connected through soldering ribbons to form a main grid-less structure, which reduces the laying of main grid lines and reduces the manufacturing cost of the cells. In addition, the main grid-less design can shorten the current carrying time. The sub-transport path and the series resistance are reduced, thereby increasing the front light-receiving area and improving the module power. However, since the soldering ribbon needs to be pre-fixed on the surface of the cell through glue first, the uncured glue itself is fluid. After the soldering ribbon is placed on the surface of the battery, the glue will flow along the extending direction of the soldering ribbon, thus causing grid lines. It is insulated by immersing glue into the soldering strip. Therefore, it is necessary to prevent glue from immersing between the soldering strip and the grid wire to improve the yield of photovoltaic modules.

According to some embodiments of the present application, an embodiment of the present application provides a cell sheet, which is beneficial to improving the yield of photovoltaic modules.

Each embodiment of the present application will be described in detail below with reference to the accompanying drawings. However, those of ordinary skill in the art can understand that in each embodiment of the present application, many technical details are provided to enable readers to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solution claimed in this application can also be implemented.

Figure 1 is a top view of a battery cell provided by an embodiment of the present application. Figure 2 is a schematic cross-sectional structural diagram along the AA1 direction in Figure 1. Figure 3 is a schematic structural diagram of various grid line groups provided by an embodiment of the present application. Figure 4 is a schematic cross-sectional structural diagram of the battery sheet in Figure 1 along the direction BB1. Figure 5 is a schematic cross-sectional structural diagram of the battery sheet in Figure 1 along the direction BB1. Figures 6 to 7 are provided by an embodiment of the present application. Top views of various battery sheets. Figures 8 to 9 are partially enlarged structural schematic diagrams of various grid line groups provided by an embodiment of the present application. Figure 10 is a top view of yet another battery sheet provided by an embodiment of the present application. Figures 11 is a schematic cross-sectional structural diagram of the battery sheet along the CC1 direction in FIG. 10 . FIG. 12 is a partially enlarged structural schematic diagram of another grid line group provided by an embodiment of the present application. The battery sheet provided by this embodiment will be described below in conjunction with the accompanying drawings. Detailed instructions are as follows:

Referring to FIGS. 1 and 2 , the cell sheet 100 includes: a substrate 101 and a passivation layer 102 , and the passivation layer 102 covers the surface of the substrate 101 . The passivation layer 102 can protect the cell chip 100 from pollution and erosion from the external environment, and can also improve the efficiency of the cell chip 100 .

The cell sheet 100 further includes: a plurality of grid line groups 103 arranged along the second direction Y. Each grid line group 103 of the plurality of grid line groups 103 includes at least two first grid lines spaced apart along the second direction Y. 113. Each of the at least two first gate lines 113 extends along the first direction X, and the first gate lines 113 are located in the passivation layer 102 and penetrate the passivation layer 102. The first grid line 113 can be used as a line connecting the internal electrodes of the battery chip 100 to draw out the carriers inside the battery chip 100 .

In some embodiments, the battery sheet 100 may be a PERC battery (Passivated Emitter and RearCell, emitter and rear passivated battery), a PERT battery (Passivated Emitter and Rear Totally-diffused cell, passivated emitter rear surface fully-diffused battery), Any one of TOPCon battery (Tunnel Oxide PassivatedContact, tunnel oxide layer passivated contact battery) and HIT/HJT battery (Heterojunction Technology, heterojunction battery). In some embodiments, the cell 100 can be a monocrystalline silicon solar cell, a polycrystalline silicon solar cell, an amorphous silicon solar cell or a multi-component compound solar cell. Specifically, the multi-component compound solar cell can be a cadmium sulfide solar cell, a gallium arsenide solar cell, Copper indium selenide solar cells or perovskite solar cells.

The material of the substrate 101 may be an elemental semiconductor material, and the elemental semiconductor material is composed of a single element, such as silicon or silicon germanium. Among them, the elemental semiconductor material can be in a single crystalline state, a polycrystalline state, an amorphous state or a microcrystalline state (a state that has both a single crystalline state and an amorphous state is called a microcrystalline state). For example, silicon can be single crystalline silicon. , at least one of polycrystalline silicon, amorphous silicon or microcrystalline silicon.

In some embodiments, the material of the substrate 101 may also be a compound semiconductor material. Common compound semiconductor materials include but are not limited to silicon germanium, silicon carbide, gallium arsenide, indium gallium, perovskite, cadmium telluride, copper indium selenide and other materials. The substrate 101 may also be a sapphire substrate, a silicon-on-insulator substrate, or a germanium-on-insulator substrate.

In some embodiments, the substrate 101 may be an N-type semiconductor substrate or a P-type semiconductor substrate. The N-type semiconductor substrate is doped with N-type doping elements. The N-type doping elements can be phosphorus (P) elements, bismuth (Bi) elements, antimony (Sb) elements or arsenic (As) elements among Group V elements. Any one. The P-type semiconductor substrate is doped with P-type elements. The P-type doping element can be any group III element such as boron (B) element, aluminum (Al) element, gallium (Ga) element or gallium (In) element. By.

In some embodiments, the substrate 101 may have opposite front and back surfaces. The front surface may be used as a light-receiving surface for receiving incident light, and the back surface may be used as a backlight surface, that is, the cell sheet 100 is a single-sided cell. In some embodiments, both the front and the back of the substrate 101 can be used as light-receiving surfaces, and both can be used to receive incident light, that is, the cell sheet 100 can be a double-sided cell.

In some embodiments, the passivation layer 102 may be a single film layer. For example, the material of the passivation layer may be aluminum oxide. The contact surface between the passivation layer 102 composed of aluminum oxide and the substrate 101 has a high fixed negative charge density. , forming an electric field with negative polarity on the surface of the substrate 101, which can provide a good field effect passivation effect for the P-type surface by shielding minority carriers (minority carriers) and electrons of the same polarity on the P-type silicon surface.

In some embodiments, the passivation layer 102 may also be a stacked film layer structure. For example, the passivation layer may be a stacked first passivation layer, a second passivation layer, and a third passivation layer. The material of the laminated film structure includes any one or more of silicon oxide, silicon nitride, silicon oxynitride, silicon carbonitride oxide, titanium oxide, hafnium oxide or aluminum oxide.

For example, the first passivation layer is a silicon oxide layer, the second passivation layer is an aluminum oxide layer, and the third passivation layer is any one or more layers of a silicon oxide layer, a silicon nitride layer, or a silicon oxynitride layer. The first passivation layer is a silicon oxide layer, which can reduce the interface state between the silicon oxide layer and the substrate, and reduce the contact resistance between the passivation layer 102 and the substrate 101 .

When the cell is a PERC cell, the first gate line can penetrate the passivation layer and contact the substrate. When the cell is a TOPCON cell, the substrate surface may also include a stacked tunnel dielectric layer and a doped conductive layer, and the first gate may penetrate the passivation layer and contact the doped conductive layer on the substrate surface. The doped conductive layer can form an energy band bend on the surface of the substrate, and the tunneling dielectric layer causes an asymmetric shift of the energy band on the surface of the substrate, causing the potential of the majority carriers (also known as majority carriers) to The barrier is lower than the potential barrier for minority carriers (also known as minority carriers) among carriers. Therefore, majority carriers can easily quantum tunnel through the tunneling medium layer, while minority carriers have a difficult time passing through the tunneling medium. layer to achieve selective transport of carriers. In addition, the tunneling dielectric layer plays a chemical passivation effect.

In some embodiments, the material of the tunneling dielectric layer may include at least one of silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, or magnesium fluoride.

In some embodiments, the material of the doped conductive layer may include at least one of amorphous silicon, polycrystalline silicon, or silicon carbide.

In some embodiments, the doped conductive layer may be doped with the same type of doping element as the substrate. For example, if the doping element type of the substrate is P type, the doping element type of the doped conductive layer may also be P type. P type; if the doping element type of the substrate is N type, the doping element type in the doped conductive layer can also be N type.

In some embodiments, the material of the first gate line 113 includes at least one of aluminum, nickel, silver, copper, gold, and graphite-based conductive materials.

It should be noted that the surface of the substrate 101 shown in FIG. 2 is a planar structure and does not constitute a limitation on the surface of the substrate 101. In some embodiments, the surface of the substrate may also have a textured surface with a pyramid structure to increase the light reflectivity of the cell sheet, thereby improving the light conversion efficiency of the cell sheet.

The following description will take an example in which the passivation layer 102 only covers one side surface of the substrate 101 . In some embodiments, the passivation layer may also cover opposite side surfaces of the substrate.

In FIG. 2, in the direction perpendicular to the surface of the substrate 101, for example, the thickness of the first gate line 113 is greater than the thickness of the passivation layer 102, which is beneficial to the electrical contact between the first gate line 113 and the shunt line 104. It does not constitute a limitation on the thickness of the first gate line 113 . In other embodiments, the thickness of the first gate line may be less than or equal to the thickness of the passivation layer.

Continuing to refer to FIG. 1 , in some embodiments, each gate line group 103 further includes a plurality of shunt lines 104 spaced apart along the first direction X, and each of the plurality of shunt lines 104 is Extending along the second direction Y, the shunt line 104 is in electrical contact with at least two first grid lines 113 in the grid line group 103, and at least part of the shunt line 104 is used to connect the soldering strips. The shunt lines 104 in the gate line group 103 are connected to at least two first gate lines 113, and at least part of the shunt lines 104 are used to connect the solder strips. Then the first gate lines 113 connected to the shunt lines 104 can be directly connected to the solder strips. Connect or connect with the solder ribbon through the shunt line 104 to improve the yield of the photovoltaic module. In addition, the shunt line 104 can also increase the welding stress between the first grid line 113 and the solder ribbon, thereby improving the stability of the photovoltaic module.

In some embodiments, the material of the shunt line 104 includes at least one of aluminum, nickel, silver, copper, gold, and graphite-based conductive materials.

In some embodiments, the material of the shunt line 104 and the first gate line 113 may be the same, so that the shunt line 104 and the first gate line 113 may be formed in the same process step. In some embodiments, the material of the shunt line 104 and the first gate line 113 may be different.

In FIG. 1 , it is taken as an example that each first gate line 113 in the gate line group 103 is connected to the shunt line 104 , and it does not constitute a relationship between the shunt line 104 and the number of the first gate lines 113 in the gate line group 103 . limited. In some embodiments, the shunt line may be in electrical contact with at least two first gate lines in the gate line group. Furthermore, in some embodiments, different shunt lines in the same gate line group may connect to different numbers of first gate lines. For example, refer to Figure 3, which shows a schematic structural diagram of three gate line groups. As shown in (a) of Figure 3, the gate line group 103a includes four first gate lines 113, and some of the shunt lines 104 can Connecting four first gate lines 113, part of the shunt lines 104 can connect to three first gate lines 113, and part of the shunt lines 104 can connect to two first gate lines 113; as shown in (b) of Figure 3, the gate lines Group 103b includes three first gate lines 113, some shunt lines 104 can connect to three first gate lines 113, and some shunt lines 104 can only connect two first gate lines 113; as shown in (c) of Figure 3 As shown, the gate line group 103c only includes two first gate lines 113, and all shunt lines 104 are connected to the two first gate lines 113.

In some embodiments, the number of first gate lines 113 in the same gate line group 103 is at least three. For example, the number of first gate lines 113 in the same gate line group 103 is 3 to 6, and may specifically be 3, 4, 5 or 6. It can be understood that the number of the first gate lines 113 in the same gate line group 103 should not be too large, so as not to cause the required length of the shunt line 104 to be too long, thereby avoiding excessive manufacturing cost of the shunt line 104 .

In some embodiments, on the same cell sheet 100, the number of first grid lines 113 in different grid line groups 103 may be the same or different. Similarly, on the same battery piece 100, the number of shunt lines 104 in different grid line groups 103 may be the same or different.

In some embodiments, referring to FIG. 4 , the shunt line 104 may be located on the surface of the passivation layer 102 . In this way, after the first gate lines 113 are formed, the shunt lines 104 can be formed on the surface of the passivation layer 102 so that the plurality of first gate lines 113 are electrically connected through the shunt lines 104 . In some embodiments, referring to FIG. 5 , the shunt line 104 can also be located in the passivation layer 102 and penetrate the passivation layer 102 , and the shunt line 104 and the first gate line 113 are an integrally formed structure. In this way, the shunt line 104 and the first gate line 113 can be formed in the same process step, thereby improving the manufacturing efficiency of the cell sheet.

It should be noted that in FIGS. 1 to 5 , it is taken as an example that the end of the shunt line 104 is flush with the edge of the outermost first gate line 113 , which does not constitute a limit to the length of the shunt line 104 . In some embodiments, referring to FIG. 6 , the end of the shunt line 104 can also exceed the edge of the outermost first gate line 113 in the gate line group 103 to ensure that the first gate line 113 can fully communicate with the shunt line. 104 Electrical contact.

In some embodiments, the number of shunt lines 104 in the same gate line group 103 may be 5 to 20, such as 5, 6, 7, 8, 9, 10, 12, or 14. , 15, 17, 19 or 20, etc. It can be understood that the shunt wires 104 are used to connect the soldering strips, and the number of the shunt wires 104 in the same grid line group 103 determines the number of soldering strips connected to the final cell piece 100. The greater the number of shunt wires 104, The number of corresponding soldering strips increases, which increases the manufacturing cost of the photovoltaic module; and the fewer the number of shunt lines 104, the more carriers the same soldering strip needs to bear, which easily leads to a decrease in the service life of the soldering strip. Therefore, the number of shunt lines 104 in the same gate line group 103 needs to be adjusted within an appropriate range.

In some embodiments, the distance between adjacent shunt lines 104 along the first direction Or 20mm. It can be understood that in order to make the distance from the carriers in the first gate line 113 to the bonding strip shorter, thereby improving the efficiency of the photovoltaic module, the distance between the shunt lines 104 needs to be set reasonably.

In some embodiments, referring to FIG. 7 , along the second direction Y, the shunt lines 104 in adjacent gate line groups 103 may be arranged in a staggered manner. In this way, after the soldering ribbon is subsequently laid on the cell sheet 100, along the second direction Y, part of the first grid lines 113 is connected to the soldering ribbon through the corresponding shunt line 104, and part of the first grid line 113 can directly contact the soldering ribbon. connect. In some embodiments, referring to FIG. 1 , shunt lines 104 in adjacent gate line groups 103 may be aligned.

In some embodiments, referring to FIG. 8 , the first grid line 113 connected to the end of the shunt line 104 includes: a first grid line body 213 and a plurality of first thickened portions 313 along the second direction Y. , the width of each first thickened portion 313 in the plurality of first thickened portions 313 is greater than the width of the first grid line body 213, and the first thickened portion 313 is used for connecting with the solder ribbon. In this way, when the photovoltaic module is subsequently formed, the contact area between the solder ribbon and the first grid line 113 is increased, which is beneficial to improving the stability of electrical transmission between the solder ribbon and the first grid line 113 .

In some embodiments, the width of the first thickened portion 313 along the first direction , 2.69mm, 3mm, 3.33mm, 3.66mm, 4mm, 4.4mm, 4.7mm, 5mm, 5.5mm or 6mm; along the second direction Y, the width of the first thickened portion 313 ranges from 0.02 to 1mm, for example 0.02mm, 0.05mm, 0.08mm, 0.1mm, 0.2mm, 0.5mm, 0.7mm, 0.9mm or 1mm. It can be understood that the first thickened portion 313 is used to increase the contact area between the solder strips in the photovoltaic module and the first grid line 113. The larger the size of the first thickened portion 313, the corresponding requirements for making the first grid line 113 are larger. The higher the slurry cost, the smaller the size of the solder strip, and the limited contact position between the solder strip and the first grid line 113. Therefore, the size of the first thickened portion 313 needs to be adjusted within a reasonable range.

In some embodiments, referring to FIG. 9 , the shunt line 104 includes: a shunt line body 204 and a plurality of widened portions 304 , each of the plurality of widened portions 304 along the first direction X. The width of 304 is larger than the width of the shunt line body 204, and the widened portion 304 is used to connect with the soldering strip. In this way, when the photovoltaic module is subsequently formed, the contact area between the solder ribbon and the shunt wire 104 is increased, which is beneficial to improving the stability of electrical transmission between the shunt wire 104 and the solder ribbon.

In some embodiments, the width of the widened portion 304 along the first direction mm, 0.26mm, 0.3mm, 0.33mm, 0.365mm, 0.4mm, 0.428mm, 0.469mm or 0.5mm; along the second direction Y, the width of the widened portion 304 ranges from 0.5 to 10mm, such as 0.5mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm. It can be understood that the widened portion 304 can increase the contact area between the soldering strip and the shunt line 104 in the photovoltaic module. The larger the size of the widened portion 304, the higher the cost of the slurry required to make the shunt line 104. Since the size of the soldering strip is fixed, the contact position between the soldering strip and the shunt line 104 is limited, and the length of the shunting line 104 along the second direction Y is related to the number of first gate lines 113 connected to the shunting line 104. Therefore , the size of the widened portion 304 can be adjusted within a reasonable range according to the total length of the shunt line 104 .

In some embodiments, referring to FIG. 10 and FIG. 11 , the cell sheet 100 further includes: a plurality of second grid lines 123 , each of the plurality of second grid lines 123 extending along the first direction X. , the second gate line 123 is located in the passivation layer 102 and penetrates the passivation layer 102 , and the second gate line 123 is also located between adjacent gate line groups 103 . That is to say, the grid line group 103 may include a second grid line 123 that is not connected to the shunt line 104 . The second grid line 123 may also be used as a line to connect the electrodes inside the battery sheet 100 , thereby connecting the internal electrodes of the battery sheet 100 . of carriers are extracted.

In some embodiments, the material of the second gate line 123 includes at least one of aluminum, nickel, silver, copper, gold, and graphite-based conductive materials.

When the cell is a PERC cell, the second grid line can penetrate the passivation layer and contact the substrate. When the cell is a TOPCON cell, the substrate surface may also include a stacked tunnel dielectric layer and a doped conductive layer, and the second gate may penetrate the passivation layer and contact the doped conductive layer on the substrate surface.

In some embodiments, the material of the first gate line 113 and the second gate line 123 are the same, so the first gate line 113 and the second gate line 123 can be formed in the same process step.

It can be understood that in both FIG. 10 and FIG. 11 , the number of the second gate lines 123 between adjacent gate line groups 103 is two, which does not constitute a second gate line between adjacent gate line groups 103 . Limited quantity of 123. In some embodiments, the number of second gate lines between adjacent gate line groups may be 1, 4, 5, etc. In addition, the number of second gate lines may be different between multiple different gate line groups.

In some embodiments, referring to FIG. 12 , the second grid line 123 includes a second grid line body 223 and a plurality of second thickened portions 323 , and along the second direction Y, among the plurality of second thickened portions 323 The width of each second thickened portion 323 is greater than the width of the second grid line body 223 , and the second thickened portion 323 is used for connecting with the solder ribbon. In this way, when the photovoltaic module is subsequently formed, the contact area between the solder ribbon and the second grid line 123 is increased, which is beneficial to improving the stability of electrical transmission between the solder ribbon and the second grid line 123 .

In some embodiments, the width of the second thickened portion 323 along the first direction , 2.69mm, 3mm, 3.33mm, 3.66mm, 4mm, 4.4mm, 4.7mm, 5mm, 5.5mm or 6mm; along the second direction Y, the width of the second thickened portion 323 ranges from 0.02 to 1mm, for example 0.02mm, 0.05mm, 0.08mm, 0.1mm, 0.2mm, 0.5mm, 0.7mm, 0.9mm or 1mm. It can be understood that the second thickened portion 323 is used to increase the contact area between the solder strips in the photovoltaic module and the second grid line 123. The larger the size of the second thickened portion 323, the corresponding requirements for making the second grid line 123 are larger. The higher the slurry cost, the smaller the size of the soldering strip is fixed, and the contact position between the soldering strip and the second grid line 123 is limited. Therefore, the size of the second thickened portion 323 needs to be adjusted within a reasonable range.

It can be understood that the different solutions provided in the above embodiments can be arbitrarily combined to obtain new embodiments if there is no conflict.

The battery sheet 100 provided in the embodiment of the present application includes a substrate 101 and a passivation layer 102 covering the surface of the substrate 101. The passivation layer 102 can protect the battery sheet 100 against pollution and erosion from the external environment, and can also improve the efficiency of the battery sheet 100. Each of the plurality of grid line groups 103 arranged along the second direction Y includes a plurality of first grid lines 113 extending along the first direction The carriers inside the battery piece 100 are extracted. The first grid line 113 in the grid line group 103 is connected through a plurality of shunt lines 104, and at least part of the shunt lines 104 are used to connect the solder ribbons, then the first grid line 113 in the grid line group 103 can be directly connected to the solder ribbons. Connect or connect with the solder ribbon through the shunt line 104 to improve the yield of the photovoltaic module.

According to some embodiments of the present application, another embodiment of the present application provides a photovoltaic module, including the cell sheet provided in the above embodiment, to improve the yield of the photovoltaic module. It should be noted that for parts that are the same as or corresponding to the above-mentioned embodiments, reference may be made to the corresponding descriptions of the foregoing embodiments and will not be described in detail below.

Figures 13 to 15 are partial schematic diagrams of various photovoltaic modules provided by another embodiment of the present application. Figures 16 to 18 are partial enlarged structural schematic diagrams of gate line groups in various photovoltaic modules provided by another embodiment of the present application. The photovoltaic module provided in this embodiment will be described in detail below with reference to the accompanying drawings, as follows:

Referring to Figures 13 to 15, the photovoltaic module also includes: a plurality of glue dots 105. The glue dots 105 are located on the surface of the cell sheet 100. On each cell sheet 100, along the second direction Y, each grid line group 103 Corresponding to one glue dot 105 , along the first direction X, each grid line group 103 corresponds to a plurality of glue dots 105 . The photovoltaic module also includes: a plurality of welding ribbons 106. Each of the plurality of welding ribbons 106 extends along the second direction Y. The welding ribbons 106 are used to connect adjacent battery sheets 100. On each battery sheet 100 , the soldering strip 106 is fixed on the surface of the battery piece 100 through a plurality of glue dots 105 arranged along the second direction Y.

Referring to Figure 13, in some embodiments, along the second direction Y, each glue dot 105 covers part of the surface of a shunt line 104; in the direction perpendicular to the surface of the cell sheet 100, the orthographic projection of the soldering strip 106 At least partially overlaps with the orthographic projection of the shunt line 104 . The glue dots 105 cover part of the surface of the shunt line 104, and the shunt line 104 plays a role in guiding the glue dots 105 to prevent the glue dots 105 from flowing on the surface of the battery piece 100, thereby preventing the glue dots 105 from impregnating the surface of the first grid line 113. This causes an insulation problem between the solder ribbon 106 and the first gate line 113 . And even if the glue dots 105 impregnate the surface of the first grid line 113, the first grid line 113 can be electrically connected to the solder ribbon 106 through the surface of the shunt line 104 that is not covered by the glue dots 105, thereby preventing the solder ribbon 106 from being connected to the first grid. Insulation between certain areas of the lines 113 causes the problem of blackening of the electroluminescent image.

Referring to FIG. 14 , in some embodiments, along the second direction Y, each glue dot 105 covers a part of the surface of a first grid line 113 that is in electrical contact with the shunt line 104 . direction, the orthographic projection of the glue dot 105 overlaps with the orthographic projection of the soldering strip 106 . In this way, the first grid line 113 covered by the glue point 105 can be connected to the solder ribbon 106 through the shunt line 104 adjacent to the glue point 105 and other first grid lines 113 in the grid line group 103. The first grid line 113 itself As a drainage line for the glue dots 105, the flow range of the glue dots 105 on the battery sheet 100 is controlled, and the current in the area of the first grid line 113 covered by the glue dots 105 can still be transmitted to the corresponding welding strip 106.

Referring to FIG. 15 , in some embodiments, along the second direction Y, each glue dot 105 can cover part of the surface of a shunt line 104 and a part of a first gate line 113 connected to the shunt line 104 surface. That is to say, the glue dots 105 cover the surface where the shunt line 104 intersects a first gate line 113 . In this way, the first grid lines 113 covered by the glue dots 105 can be connected to the solder ribbons 106 through the surface of the shunt line 104 that is not covered by the glue dots 105, and each solder ribbon 106 can be electrically connected to each first grid line 113. , in the subsequent inspection process of the cell chip 100, there will be no problem that the partial area of the first grid line 113 cannot be connected to the solder ribbon 106, causing the electroluminescence image to turn black.

It can be understood that the glue dots 105 can cover the intersection between the shunt line 104 and any first grid line 113 , and the glue dots 105 in the same grid line group 103 can cover the intersection between the same first grid line 113 and multiple shunts. The positions where the lines 104 intersect, or the multiple glue dots 105 cover the positions where different first grid lines 113 and different shunt lines 104 intersect. The position of the glue point 105 can be adjusted according to the actual situation.

It should be noted that FIG. 13 to FIG. 15 only show a schematic structural diagram of one cell sheet. The photovoltaic module may also include multiple cell sheets, and adjacent cell sheets are connected by soldering strips. For example, the front side of the battery sheet has a first electrode, and the back side of the battery sheet has a second electrode. The first electrode is one of the positive electrode or the negative electrode, and the second electrode is the other one of the positive electrode or the negative electrode. Multiple battery sheets are Arranged face up along the second direction, the first electrode of any cell sheet is electrically connected to the second electrode of the adjacent cell sheet through a connecting member, and the same connecting member is located on both sides of the adjacent cell sheet; in some embodiments , the front side of the battery sheet has a first electrode, and the back side of the battery sheet has a second electrode. The first electrode is one of the positive electrode or the negative electrode, and the second electrode is the other one of the positive electrode or the negative electrode. Multiple battery sheets are arranged along the first electrode. The front and back faces are alternately arranged in two directions. The first electrode of any cell sheet is electrically connected to the second electrode of an adjacent cell sheet through a connecting member, and the same connecting member is located on the same side surface of the adjacent cell sheet.

In some embodiments, the back side of the battery sheet has a first electrode and a second electrode, the first electrode is one of the positive electrode or the negative electrode, the second electrode is the other one of the positive electrode or the negative electrode, and the third electrode on any battery sheet One electrode is electrically connected to the second electrode on the adjacent battery sheet on one side through the connecting component, and the second electrode on the battery sheet is electrically connected to the first electrode on the adjacent battery sheet on the other side through the connecting component. That is to say, the cell is a full back electrode contact crystalline silicon solar cell (Interdigitated back contact, IBC). IBC cell refers to a back-junction back-contact solar cell in which the positive and negative metal electrodes are arranged in an interdigitated manner on the backlight surface of the battery. structure, its PN junction and electrodes are located on the back of the battery, that is, the electrodes in the emitter area and base area of the IBC battery are both on the back, and the front is not blocked by grid lines, which can improve the photoelectric conversion performance of the battery.

In some embodiments, the welding ribbons may include bus ribbons and interconnection ribbons. The bus ribbons are used to connect photovoltaic cell strings and junction boxes, and the interconnection ribbons are used to connect adjacent cell sheets.

In some embodiments, the soldering strip may be composed of a conductive layer and a soldering layer covering the surface of the conductive layer. The conductive layer may be made of conductive materials such as copper, nickel, gold, silver, etc., or alloy materials with low resistivity. ; The materials of the welding layer include materials with lower melting points such as tin-zinc alloy, tin-bismuth alloy or tin-indium alloy.

In some embodiments, the glue dots 105 can be formed using acrylate glue, polymer glue, hot melt glue or polymer adhesive. The type or curing method of the glue dots 105 can be adjusted according to the actual needs of the photovoltaic module. For example, the glue dots 105 can use low-temperature glue, and the corresponding glue dots 105 will have a lower curing temperature to reduce the degree of thermal stress on the cell sheet 100. , to avoid problems such as thermal warping of the battery cells 100 due to large thermal stress.

In some embodiments, the width of the glue dot 105 ranges from 0.1 to 10 mm along the second direction It can be understood that when the glue dot 105 covers part of the surface of the shunt line 104, the width of the glue dot 105 in the second direction Y can be determined according to the length of the shunt line 104, and the length of the shunt line 104 is related to the length of the shunt line 104. It is related to the number of first gate lines 113 connected to the line 104. For example, when the number of first gate lines 113 connected to the shunt line 104 is three, the width of the glue dot 105 can be between 0.1 and 3 mm; when the number of first gate lines 113 connected to the shunt line 104 is four. , the width of the glue dot 105 can be between 0.1 and 6mm; when the number of first grid lines 113 connected to the shunt line 104 is 5, the width of the glue dot 105 can be between 0.1 and 8mm; when the shunt line 104 is connected When the number of first grid lines 113 is six, the width of the glue dots 105 can be between 0.1 and 10 mm.

It can be understood that when the number of first gate lines 113 connected to the shunt line 104 is greater, the length of the shunt line 104 is longer, and the width range of the corresponding glue dot 105 extending along the shunt line 104 is larger, even if the glue dot is 105 covers part of the surface of the first grid line 113 , and the first grid line 113 can still be connected to the solder ribbon 106 through the shunt line 104 . However, the width of the glue dot 105 still needs to be within an appropriate range to keep part of the surface of the shunt line 104 in electrical contact with the solder ribbon 106 . Therefore, the size of the glue dot 105 needs to be within an appropriate range.

Along the first direction It can be understood that when the glue dot 105 covers the surface of the first grid line 113 , the width of the glue dot 105 along the first direction X can be determined according to the distance between the shunt lines 104 .

For ease of explanation, in FIGS. 13 to 15 , the shape of the glue dot 105 is circular as an example, which does not constitute a limitation on the shape of the glue dot 105 . In some embodiments, the shape of the glue dot 105 may also be an oval or a rectangle. Since the glue dots 105 may also extend in the direction of the shunt line 104, the extended thickness shape of the glue dots 105 may also be an irregular pattern.

It should be noted that the size of the above-mentioned glue dot 105 is the size of the glue dot 105 when dispensing glue, that is, the size when the welding strip 106 has not yet covered the glue dot 105. When the welding strip 106 covers the glue dot 105, the glue spot 105 is The point 105 may extend along the extension direction of the shunt line 104 or the extension direction of the welding strip 106, and the size of the extended glue point 105 cannot be fixed. Therefore, by determining the dispensing size of the glue dot 105, the expanded size of the glue dot 105 is controlled to be within an appropriate range.

In some embodiments, referring to FIG. 16 , when the first grid line 113 connected to the end of the shunt line 104 includes a first grid line body 213 and a first thickened portion 313 , the glue dots 105 are on the surface of the battery sheet 100 The orthographic projection of does not overlap with the orthographic projection of the first thickened portion 313 on the surface of the cell sheet 100 . In this way, it can be avoided that the glue dots 105 cover the surface of the first thickened portion 313 and cause insulation between the first gate line 113 and the solder ribbon 106 .

In some embodiments, referring to FIG. 17 , when the shunt line 104 includes a shunt line body 204 and a widened portion 304 , the orthographic projection of the glue dot 105 on the surface of the battery sheet 100 is the same as the orthogonal projection of the widened portion 304 on the surface of the battery sheet 100 . The projections do not overlap. In this way, the problem of insulation between the shunt line 104 and the soldering strip 106 caused by the glue dots 105 covering the surface of the widened portion 304 can be avoided.

In some embodiments, referring to FIG. 18 , when the cell sheet 100 further includes a second grid line 123 , and the second grid line 123 includes a second grid line body 223 and a second thickened portion 323 , the second thickened portion 323 The orthographic projection on the surface of the battery chip 100 overlaps with the orthographic projection of the soldering strip 106 on the surface of the battery chip 100 . In this way, the contact area between the second grid line 123 and the soldering strip 106 can be increased, thereby improving the electrical transmission efficiency between the second grid line 123 and the soldering strip 106 .

It can be understood that the positions of the glue dots 105 can be combined with the above-mentioned different embodiments and the different structures of the battery sheets 100 and can be arbitrarily combined without conflict to obtain new embodiments.

The photovoltaic component may also include: an encapsulation layer. In some embodiments, the encapsulation layer includes a first encapsulation layer and a second encapsulation layer. The first encapsulation layer covers one of the front or back sides of the cell sheet, and the second encapsulation layer covers the cell. The other one of the front side or the back side of the sheet, specifically, at least one of the first encapsulation layer or the second encapsulation layer can be ethylene-vinyl acetate copolymer (EVA) film, polyethylene octene co-elastomer (POE) Plastic film or organic encapsulating film such as polyvinyl butyral (PVB) film.

The photovoltaic module may also include a cover plate. In some embodiments, the cover plate may be a glass cover plate, a plastic cover plate, or other cover plate with a light-transmitting function. Specifically, the surface of the cover facing the encapsulation layer can be a concave and convex surface, thereby increasing the utilization of incident light. In some embodiments, the cover plate includes a first cover plate and a second cover plate, the first cover plate is opposite to the first encapsulation layer, and the second cover plate is opposite to the second encapsulation layer.

The photovoltaic module provided by the embodiment of the present application includes the cell sheet 100 described in the above embodiment. The glue dots 105 located on the surface of the cell sheet 100 cover part of the surface of a shunt line 104, and/or the glue dots 105 cover the shunt line 104. If the flow line 104 electrically contacts a part of the surface of the first grid line 113, the shunt line 104 or the first grid line 113 can be used as a drainage line for the glue dot 105 to prevent the glue dot 105 from flowing on the surface of the battery piece 100, even if the glue dot 105 impregnates the surface of the first grid line 113. The first grid line 113 can also be electrically connected to the soldering ribbon 106 through the corresponding shunt line 104, thereby avoiding insulation between the soldering ribbon 106 and a certain area of the first grid line 113. The problem of blackening of electroluminescent images. In addition, the soldering ribbon 106 is fixed on the surface of the battery piece 100 through the glue dots 105, so there is no need to use infrared welding, which avoids problems such as stress warping of the battery piece 100 caused by high temperature, resulting in cracks or fragments, and thus in the subsequent lamination process. , the temperature and pressure of the laminator can be used to help the solder ribbon 106 be combined with the shunt line 104 or the first grid line 113 to form a main grid-less structure, shorten the carrier transport path and reduce the series resistance.

Those of ordinary skill in the art can understand that the above-mentioned embodiments are specific examples for implementing the present application, and in actual applications, various changes can be made in form and details without departing from the spirit and spirit of the present application. scope.

Claims (10)

1. A battery sheet, characterized in that it includes: base; Passivation layer, the passivation layer covers the surface of the substrate; A plurality of gate line groups arranged along the second direction, each of the plurality of gate line groups including at least two first gate lines spaced apart along the second direction, the at least two first gate lines Each first gate line in a gate line extends along the first direction, and the first gate line is located in the passivation layer and penetrates the passivation layer; each of the gate line groups also includes a gate line along the passivation layer. A plurality of shunt lines arranged at intervals in the first direction, each of the plurality of shunt lines extending along the second direction, and at least one of the shunt lines and the gate line group is The two first grid lines are in electrical contact, and at least part of the shunt lines are used to connect the soldering strips. 2. The battery sheet according to claim 1, wherein the shunt line is located on the surface of the passivation layer; or, the shunt line is located in the passivation layer and penetrates the passivation layer. , and the shunt line and the gate line are an integrally formed structure. 3. The battery sheet according to claim 1, characterized in that, along the second direction, the shunt lines in the adjacent grid line groups are arranged in a staggered manner, or the adjacent grid lines are arranged in a staggered manner. The shunt lines in the group are aligned. 4. The battery sheet according to claim 1, wherein the number of the first grid lines in the same grid line group is 3 to 6. 5. The battery sheet according to claim 1, wherein the number of shunt lines in the same grid line group is 5 to 20. 6. The battery sheet according to claim 1, wherein the distance between adjacent shunt lines along the first direction ranges from 6 to 20 mm. 7. The battery sheet according to claim 1, wherein the first grid line connected to the end of the shunt line includes: a first grid line body and a plurality of first thickened portions. Along the second direction, the width of each first thickened portion in the plurality of first thickened portions is greater than the width of the first grid line body, and the first thickened portion is used to communicate with the first thickened portion. Described solder ribbon connection. 8. The battery sheet according to claim 1, wherein the shunt line includes: a shunt line body and a plurality of widened portions, and along the first direction, the plurality of widened portions The width of each widened portion is greater than the width of the shunt line body, and the widened portion is used to connect with the soldering strip. 9. The battery sheet according to claim 1, further comprising: a plurality of second grid lines, each of the plurality of second grid lines extending along the first direction. , the second gate line is located in the passivation layer and penetrates the passivation layer, and the second gate line is also located between adjacent gate line groups. 10. A photovoltaic module, characterized by comprising: A plurality of battery sheets according to any one of claims 1 to 9; A plurality of glue points are located on the surface of the battery sheet. On each battery sheet, along the second direction, each grid line group corresponds to one of the glue points, wherein , in the second direction, each of the glue points covers a part of the surface of the shunt line, and/or, each of the glue points covers a part of the surface of the shunt line that is in electrical contact with the shunt line. Part of the surface of the first grid line; A plurality of welding ribbons, each of the plurality of welding ribbons extending along the second direction, the welding ribbons are used to connect adjacent battery sheets, and on each of the battery sheets, the The soldering strip is fixed on the surface of the battery sheet through a plurality of glue dots arranged along the second direction.