CN104576792A - Method for assembling solar cells, solar cell modules and bypass diodes - Google Patents

Abstract

The invention provides a solar cell, a solar cell module and an assembling method of a bypass diode. The solar cell piece comprises: the first welding strip and the second welding strip are arranged on different surfaces of the substrate; the diode chip further comprises at least one diode chip, wherein a first electrode and a second electrode of the diode chip are arranged on two opposite surfaces, the first electrode of the diode chip is electrically connected to the first welding strip, and the second electrode of the diode chip is electrically connected to the second welding strip. The solar module bypass diode has the advantages that the corresponding bypass diode is arranged for each solar cell piece by changing the design and assembly mode of the solar module bypass diode, so that when partial solar cell pieces are shielded, only the shielded cells are isolated from the main circuit, the temperature of the solar module when hot spots occur is greatly reduced, the use reliability is improved, and the maximization of the output power is ensured.

Description

Method for assembling solar cells, solar cell modules and bypass diodes

technical field

The invention relates to the field of solar cell modules, in particular to a method for assembling solar cells, solar cell modules and bypass diodes, and the scope of application is crystalline silicon cells (P-type, N-type) and corresponding components.

Background technique

A solar cell module is usually formed by combining multiple solar cells in parallel or in series, and arranged in an array. For multiple solar cells or components connected in series, the current passing through them is determined by the solar cell or component with the smallest passing current capability. Therefore, when a solar cell or component is damaged or blocked, the current passing capacity of the cell will be reduced, resulting in reverse bias, and may be broken down by other normal working solar cells or components on the circuit .

A common method in the prior art is to use a bypass diode in parallel at both ends of the solar cell module. When the solar cell module is damaged or blocked and becomes a load, the voltage across the bypass diode rises rapidly and Forward conduction occurs so that the current flows through the bypass diode instead of the solar cell module, thus protecting the solar cell module.

Taking 60 solar cells in the prior art as an example to form a solar cell module, it usually includes three groups of 20 solar cells connected in series, and a bypass diode is configured for each group of solar cells connected in series. Therefore, each solar cell module needs to be equipped with three bypass diodes, and the maximum reverse bias voltage of each bypass diode is about 12V (the output voltage of each solar cell is 0.6V). When one of the 20 solar cells in each group is damaged or blocked, the bypass diode will shunt the current of the group of 20 solar cells connected in series to separate it from the main circuit. In engineering, a special junction box is required to connect the bypass diode to one side of the solar module. It is also possible to form a solar cell module by 96, 72 or 54 solar cells, so that each group contains 32, 24 or 18 solar cells connected in series.

Therefore, the assembly and maintenance of the bypass diodes are costly and difficult. Moreover, each group of solar cell modules can only have one group of bypass diodes, which requires high voltage resistance, and is an urgent problem to be solved in the prior art.

Contents of the invention

The technical problem to be solved by the present invention is to provide an assembly method of a solar cell, a solar cell module and a bypass diode, which can more effectively provide bypass protection for the solar cell.

In order to solve the above problems, the present invention provides a solar battery sheet, including: a substrate; The group welding ribbon includes a plurality of second welding ribbons, the first welding ribbon and the second welding ribbon are arranged on different surfaces of the substrate; further includes at least one diode chip, the first electrode and the second electrode of the diode chip It is arranged on two opposite surfaces, and the first electrode of the diode wafer is electrically connected to the first welding strip, and the second electrode of the diode wafer is electrically connected to the second welding strip.

As an optional configuration, the first soldering strip is electrically connected to the negative grid line of the substrate, and the second soldering strip is electrically connected to the positive grid line of the substrate; the first electrode of the diode is the positive pole, so The second electrode is a negative electrode. It can also be configured such that the first soldering strip is electrically connected to the positive grid line of the substrate, and the second soldering strip is electrically connected to the negative grid line of the substrate; the first electrode of the diode is the negative pole, and the second electrode is the positive electrode.

The advantage of the above technical solution is that a bypass diode chip can be configured for each solar cell substrate, which realizes what is called "a solar cell corresponding to a parallel diode chip protection (ECEDP: each cell each diode protection)" or It is called "one parallel diode chip corresponds to one solar cell protection (ODOCP: one diode one cell protection)" protection method, so that in the case of a solar cell failure, only the solar cell is disconnected from the main circuit. The remaining solar cells in the battery string that are working normally can still generate electricity.

The above-mentioned connection between the diode chip and the soldering strip can be realized through various arrangements, including but not limited to setting the diode chip in a through hole in the substrate, between two soldering strips on one side of the substrate, and in a soldering hole. One side of the belt is connected with the welding belt through the connecting structure, etc.

As an optional arrangement, the first soldering strip and the second soldering strip are arranged symmetrically with respect to the substrate, and the second soldering strip has an extension, and the diode chip is further arranged on the Between the extension section and the first welding strip, the first electrode of the diode chip is attached to the first welding strip, and the second electrode of the diode chip is attached to the second welding strip.

As an optional setting method, it further includes a second extended grid line, the second extended grid line is arranged on the surface of the substrate on which the second welding strip is provided, and is connected to the second welding strip, so The second electrode of the diode chip is further connected to the second extended grid line through a second electrode connecting piece, and the first electrode of the diode chip is further directly connected to the first welding strip through a first electrode connecting piece .

As an optional arrangement, it further includes a first extended grid line and a second extended grid line, the first extended grid line and the second extended grid line are respectively arranged on different surfaces of the substrate, and respectively Connected with the first soldering strip and the second soldering strip, the first electrode of the diode chip is further connected to the first extended grid line through a first electrode connecting piece, and the second electrode of the diode chip is further connected to the first electrode through a first The two electrode connecting pieces are connected to the second extended grid lines.

As an optional arrangement, the first soldering strip and the second soldering strip are arranged symmetrically with respect to the substrate, and the substrate further includes a through hole, the through hole is located between the first soldering strip and the In the area covered by the second soldering strip, the diode chip is embedded in the through hole and electrically isolated from the substrate by an insulating layer, and the first electrode of the diode chip is attached to the first soldering strip, so that The second electrode of the diode chip is bonded to the second soldering tape.

The present invention further provides a solar cell module, comprising an array composed of a plurality of solar cells, and at least one of the above-mentioned solar cells is included in the array.

The present invention further provides a method for assembling a bypass diode, comprising the steps of: providing a substrate, the substrate including an anode surface and a cathode surface; forming at least one through hole in the substrate; The side wall is covered with an insulating layer; a diode chip is embedded in the through hole, the anode of the diode chip is exposed to the negative electrode surface of the substrate, and the negative electrode of the diode chip is exposed to the positive electrode surface of the substrate.

In the bypass assembly of solar cell modules and diode chips in the prior art, whether the bypass diode chip is turned on or not depends only on whether the bias voltage generated by the solar cell itself is large enough, and does not need to generate a higher negative bias voltage To resist the positive pressure generated by other normal working solar cells in the battery string. For example, in 60 conventional components, the problematic solar cells will simultaneously generate the positive voltage to overcome 19 solar cells and make the diode chip turn-on voltage. In order to make the series diode chips conduct, the solar cell in question needs to generate at least a negative bias voltage greater than the above (this means that the solar cell in question will flow through a larger reverse current as a load and generate more heat). In the same way, in order to make the 72-piece polycrystalline solar module series diode chips conduct, the problematic solar cells must generate a higher bias voltage to overcome the voltage of 23 solar cells to make the diode chips conduct and protect the problem solar cells piece.

In the present invention, each solar battery slice is connected in parallel by a diode chip, and such an assembly has a more sensitive hot spot response capability than a traditional solar assembly. The shielding area experiment for generating hot spots also verifies that the component of the invention has a smaller shielding area and can start the conduction of the bypass diode chip. (The hot spot shading area of solar cells and the efficiency of solar cells are related, and only a range value can be given)

Components of the invention 60 traditional components 72 traditional components The minimum shaded area threshold that enables the diode to turn on 5% 10% 15% When a hot spot occurs, the battery sheet covers the area 10% 15%+ 20%- When the hot spot occurs, the maximum temperature of the component 52.3 120 130 When the hot spot occurs, the maximum temperature of the bypass diode 43 40～50 40～50

Therefore, the advantage of the present invention is that, by changing the design and assembly method of the bypass diode chip of the solar cell module, a corresponding bypass diode chip is provided for each solar cell, which can ensure that when part of the solar cell is blocked , only the shaded solar cells are isolated from the main circuit, while the rest of the normal working solar cells in the solar cell string can still generate electricity, which greatly reduces the temperature of the solar cell components when hot spots occur, and improves the components It is a more effective way of protection; and since both the diode chip and the substrate are semiconductor materials, the reinforcement of the interface between the diode chip and the ribbon and the reinforcement of the substrate and the solder The reinforcement between the belts can be completed simultaneously by the same process, so no additional reinforcement material and reinforcement process will be added. In addition, there is no need to arrange a diode chip in the junction box using this component, so the wiring of the component is more convenient.

Description of drawings

Accompanying drawing 1A is a schematic structural view of the first specific embodiment of the solar cell sheet of the present invention;

Shown in accompanying drawing 1B is the equivalent circuit diagram of the structure shown in accompanying drawing 1A;

Figure 2A is a schematic diagram of a specific embodiment of using the solar cells shown in Figure 1A in series to form a battery string, and then forming a solar module;

Shown in accompanying drawing 2B is the equivalent circuit diagram of the structure shown in accompanying drawing 2A;

Accompanying drawing 3A and 3B are the structural schematic diagrams of the second specific embodiment of the solar battery sheet of the present invention;

Figures 4A and 4B are structural schematic diagrams of a third specific embodiment of the solar cell sheet of the present invention;

Accompanying drawing 5 is a structural schematic diagram of a fourth specific embodiment of the solar battery sheet according to the present invention;

Shown in accompanying drawing 6 is the step schematic diagram of the specific embodiment of the structure manufacturing method shown in accompanying drawing 5;

Accompanying drawing 7A to accompanying drawing 7E are process diagrams of the method shown in accompanying drawing 6.

Detailed ways

The specific implementation of the solar battery sheet, solar battery module and bypass diode assembly method provided by the present invention will be described in detail below with reference to the accompanying drawings.

In the following specific implementation manners, the first welding ribbon is uniformly configured as a negative electrode ribbon, electrically connected to the negative electrode grid line of the substrate, and the second solder ribbon is configured as a positive electrode electrode ribbon, electrically connected to the positive electrode grid line of the substrate; The first electrode of the diode chip is configured as an anode, and the second electrode is configured as a cathode.

In other specific implementation manners, the first welding ribbon can also be configured as a positive electrode ribbon, which is electrically connected to the positive grid line of the substrate, and the second solder ribbon is configured as a negative electrode ribbon, which is connected to the negative electrode grid line of the substrate. Electrical connection; the first electrode of the diode wafer is configured as a negative pole, and the second electrode is configured as a positive pole.

Firstly, a first specific embodiment of the solar battery sheet of the present invention is given in conjunction with the accompanying drawings.

Referring to accompanying drawing 1A, it is a schematic structural diagram of this specific embodiment. The solar battery sheet 1 of this specific embodiment includes a substrate 10, and a first welding strip 11 and a second welding strip 12 are respectively arranged on different surfaces of the substrate 10, and the first welding strip 11 and the second welding strip 12 are opposite to each other. symmetrically arranged on the substrate. The solar cell 1 can be an N-type cell or a P-type cell. In FIG. 1A , a solar cell made of a P-type silicon chip is taken as an example. The first welding strip 11 is electrically connected to the negative grid line (not shown in the drawings) of the substrate 10 , and the second welding strip 12 is electrically connected to the positive grid line (not shown in the drawings) of the substrate 10 . The second welding strip 12 has an extension section (not shown in the drawings), that is, the second welding strip 12 extends to the outside of the edge of the substrate 10 . The first ribbon 11 itself needs to be extended and connected to the positive grid line adjacent to another solar cell. The material of the first welding strip 11 and the second welding strip 12 is a metal that can be welded with grid lines. A diode chip 13 is further arranged between the extension section of the second welding strip 12 and the first welding strip 11, and the anode 131 of the diode chip 13 is attached to the first welding strip 11, and the negative pole of the diode chip 13 132 is attached to the second soldering strip 12 . The lamination can be realized by welding or bonding with conductive tape. The first welding strips 11 and the second welding strips 12 can be one set or multiple sets, and if there are multiple sets, at least one set should be configured according to the structure described in the specific embodiment. The diode chip 13 refers to a chip structure including a diode chip structure cut directly from a wafer, and is directly used without packaging. The wafer and the substrate 10 used to make the diode chip 13 usually have similar thicknesses, so that the side-by-side clamping structure shown in FIG. 1A can be realized. Since both the diode chip 13 and the substrate 10 are made of semiconductor materials, the reinforcement of the interface between the diode chip 13 and the solder strip and the reinforcement between the substrate 10 and the solder strip can be completed simultaneously by the same process, so no additional reinforcement materials will be added. and reinforcement process. The cross-sectional shape of the diode chip 13 along the direction perpendicular to the drawing is selected from any one of rectangle, circle, ellipse and polygon.

The equivalent circuit diagram of the structure shown in FIG. 1A is shown in FIG. 1B , the solar cell 1 and the diode chip 13 are connected in parallel, so that the diode chip 13 acts as a bypass diode for a single solar cell 1 .

In other specific implementation manners, a plurality of diode chips 13 can be clamped in parallel between the first soldering ribbon 11 and the second soldering ribbon 12, so as to enhance the passability of the bypass current.

FIG. 2A is a schematic diagram of a specific embodiment of using the solar cell sheets 1 shown in FIG. 1A to be connected in series to form a battery string, and then form a solar module. The first soldering ribbon 11 on the substrate 10 of the solar cell 1 is the same soldering ribbon as the second soldering ribbon 202 on the substrate 200 of the adjacent solar cell 20 , while the other side is adjacent to the substrate 210 of the solar cell 21 The first soldering ribbon 211 is the same soldering ribbon as the second soldering ribbon 12 on the substrate 10, thereby forming a battery string connected in series. And the solar cell 20 and the solar cell 21 may also have similar diode chips 203 and 213 connected in parallel.

The equivalent circuit diagram of the structure shown in Fig. 2A is shown in Fig. 2B, and each solar cell is provided with a corresponding bypass diode. In this way, it can be ensured that in the case of failure of a certain solar cell, only the solar cell is isolated from the main circuit, while the remaining normal working solar cells in the battery string can still generate electricity. And since one bypass diode only corresponds to one solar cell, the withstand voltage requirement of the bypass diode is greatly reduced. For silicon-based solar cells, the maximum reverse bias voltage of the bypass diode is only 0.6V. Since the market price of a diode is consistent with its maximum reverse bias value, although the number of diodes has increased compared to a string of solar cells with a bypass diode, the cost of a single diode greatly reduced. And the plane area of the unpackaged diode chip is very small, only a few square millimeters, so it can be arranged in the gap between the solar cell arrays without increasing the volume of the whole solar cell module.

Next, a second specific embodiment of the solar battery sheet of the present invention will be given with reference to the accompanying drawings.

Referring to the accompanying drawings 3A and 3B, it is a schematic structural view of the solar battery sheet according to this specific embodiment, including a substrate 30, and a first soldering strip 31 and a second soldering strip 32 are respectively arranged on different surfaces of the substrate 30, wherein the attached FIG. 3A is a view from the first ribbon 31 side, and FIG. 3B is a view from the second ribbon 32 side. In the above two views, the structures on the opposite side of the back side are indicated by dotted lines. The first welding strip 31 and the second welding strip 32 may be arranged symmetrically with respect to the substrate 30 . The first welding strip 31 is electrically connected to the negative grid line of the substrate 30 , and the second welding strip 32 is electrically connected to the positive grid line of the substrate 30 .

Referring to FIG. 3B , the surface where the second welding ribbon 32 is located further includes a second extended grid line 321, and the second extended grid line 321 is arranged on the substrate 30 provided with the second welding ribbon 32. surface, and connected with the second ribbon 32. Continue to refer to shown in accompanying drawing 3B, the cathode of a diode chip 33 is further connected to the second extended grid line 321 through a second electrode connecting piece 342 (i.e. the negative electrode connecting piece), and then connected to the second welding strip 32 and The positive grid line of the substrate 30 . The second extended grid lines 321 can be pasted on the surface of the substrate 30 by metal strips, or can be coated on the surface of the substrate 30 by coating conductive paste. Referring to Figure 3A, the anode of the diode chip 33 is further directly connected to the first soldering strip 31 through a first electrode connecting piece 341 (i.e., the positive connecting piece), and then connected to the negative grid line of the substrate 30 . The material of the first electrode connecting piece 341 (ie, the positive electrode connecting piece) and the second electrode connecting piece 342 (ie, the negative electrode connecting piece) can be metal or other conductive materials, which can be the same as the material of the solder strip on the surface of the substrate 30 .

The second extended grid lines 321 may further be printed on the surface of the positive electrode of the substrate (also the surface where the second soldering strip 32 is located) through screen printing. The overlapping lines are printed by screen printing as the second extended grid lines 321 , so as to be welded to the first electrode connecting piece 341 (ie, the positive electrode connecting piece).

Since the two grid lines of any solar cell in the battery string are connected to the opposite side grid lines of the adjacent cell on different sides by the same welding ribbon (refer to Figure 2A), so each side has at least A ribbon should extend beyond the boundaries of the cell. This specific embodiment is aimed at the situation that the first soldering strip 31 extends beyond the boundary of the battery sheet. The second soldering strip 32 extends beyond the cell at the other end of the cell. If a diode chip 33 is provided on this side, it is only necessary to reverse the positive and negative electrodes described in the above specific embodiment.

The diode chip 33 refers to a chip structure including a diode structure cut directly from the wafer, and is directly used without packaging. The wafer and the substrate 30 used to make the diode chip 33 usually have similar thicknesses, so that the side-by-side clamping structure of the substrate 30 and the diode chip 33 shown in FIGS. 3A and 3B can be realized smoothly. Because the diode chip 33 and the substrate 30 are all semiconductor materials, the reinforcement of the interface between the diode chip 33 and the two connecting pieces and the reinforcement between the substrate 30 and the two soldering strips can be completed simultaneously by the same process, so it will not increase Additional reinforcement materials and reinforcement processes.

In other specific embodiments, a plurality of diode chips 33 can be arranged in parallel, and electrically connected to the welding strip through the same or different connection pieces in series or parallel. The series connection can increase the withstand voltage capability of the bypass, and parallel The method can enhance the current passing capacity of the bypass.

The equivalent circuit diagram of the above structure and the structural schematic diagram and equivalent circuit diagram after forming the solar cell module are similar to those of the first embodiment, so they are not described again. Similar to the previous specific embodiment, the structure provided by this specific embodiment can also ensure that when a certain solar cell fails, only the solar cell is isolated from the main circuit, while the rest of the battery string works normally. The solar cell sheet can still generate electricity, and the plane area of the unpackaged diode chip is very small, only a few square millimeters, and the length of the connecting piece can also be set to a few millimeters to meet the insulation requirements, so it can be set in the solar cell In the gaps between sheet arrays, the volume of the entire solar cell module will not be increased.

Next, a third specific embodiment of the solar battery sheet of the present invention will be given with reference to the accompanying drawings.

Referring to Figures 4A and 4B , it is a schematic structural view of the solar battery sheet described in this specific embodiment. Including a substrate 40, a first soldering strip 41 and a second soldering ribbon 42 are respectively arranged on different surfaces of the substrate 40, wherein accompanying drawing 4A is a view from one side of the first soldering ribbon 41, and accompanying drawing 4B is a view from the second soldering ribbon 41. View from side 42. In the above two views, the structures on the opposite side of the back side are indicated by dotted lines. The first welding strip 41 and the second welding strip 42 may be arranged symmetrically with respect to the substrate 40 . The first welding strip 41 is electrically connected to the negative grid line of the substrate 40 , and the second welding strip 42 is electrically connected to the positive grid line of the substrate 40 .

Referring to FIG. 4A , the surface where the first welding ribbon 41 is located further includes a first extended grid line 411, and the first extended grid line 411 is arranged on the substrate 40 where the first welding ribbon 41 is arranged. and connected to the first soldering strip 41 , and the anode of a diode chip 43 is further connected to the first extended grid line 411 through a first electrode connecting piece 441 (ie, the positive connecting piece). Referring to FIG. 4B , the surface where the second welding ribbon 42 is located further includes a second extended grid line 421, and the second extended grid line 421 is arranged on the substrate 40 where the second welding ribbon 42 is arranged. The surface of the diode chip 43 is connected to the second soldering strip 42, and the cathode of the diode chip 43 is connected to the second extended grid line 421 through a second electrode connecting piece 442 (ie, the negative connecting piece). The first extended grid lines 411 and the second extended grid lines 421 can be attached on the surface of the substrate 40 by metal strips, or can be formed on the surface of the substrate 40 by coating (screen printing) conductive paste. The material of the first electrode connecting piece 441 (ie, the positive electrode connecting piece) and the second electrode connecting piece 442 (ie, the negative electrode connecting piece) can be metal or other conductive materials, which can be the same as the material of the solder strip on the surface of the substrate 40 . In order to improve the insulation performance between the first electrode connecting piece 441 (ie, the positive connecting piece) and the second electrode connecting piece 442 (ie, the negative connecting piece), in this specific embodiment, the first electrode connecting piece 441 (ie, the positive connecting piece) sheet) further includes a bend at one end connected to the diode chip 43, so that the body portion of the second electrode connection sheet 442 (ie, the negative electrode connection sheet) is connected to the body portion of the first electrode connection sheet 441 (ie, the positive electrode connection sheet). There is a distance L between them to improve the insulation between them.

Since the two ribbons of a solar cell need to be connected to adjacent solar cells on different sides (refer to FIG. 2A ), at least one ribbon should extend beyond the boundary of the solar cell on each side. This specific embodiment is aimed at the situation that the second soldering strip extends beyond the boundary of the solar battery sheet. For the case where the first soldering strip extends beyond the solar cells, it is only necessary to reverse the positive and negative electrodes described in the above specific implementation manners.

The diode chip 43 refers to a chip structure including a diode structure that is directly cut from the wafer, and is used directly without packaging. The wafer and the substrate 40 used to make the diode chip 43 usually have similar thicknesses, so that the side-by-side clamping structure of the substrate 40 and the diode chip 43 shown in FIGS. 4A and 4B can be realized smoothly. Because the diode chip 43 and the substrate 40 are all semiconductor materials, the reinforcement of the interface between the diode chip 43 and the two connecting pieces and the reinforcement between the substrate 40 and the two welding strips can be completed simultaneously by the same process, so there will be no increase. Additional reinforcement materials and reinforcement processes.

In other specific embodiments, a plurality of diode chips 43 can be arranged in parallel, and electrically connected to the soldering strips through the same or different connecting pieces in series or in parallel. The method can enhance the current passing capacity of the bypass.

The equivalent circuit diagram of the above structure and the structural schematic diagram and equivalent circuit diagram after forming the solar cell module are similar to those of the first embodiment, so they are not described again. Similar to the previous specific embodiment, the structure provided by this specific embodiment can also ensure that when a certain solar cell fails, only the solar cell is isolated from the main circuit, while the rest of the battery string works normally. The solar cell sheet can still generate electricity, and the plane area of the unpackaged diode chip is very small, only a few square millimeters, and the length of the connecting piece can also be set to a few millimeters to meet the insulation requirements, so it can be set in the solar cell In the gaps between sheet arrays, the volume of the entire solar cell module will not be increased.

Next, a fourth specific embodiment of the solar battery sheet of the present invention will be given with reference to the accompanying drawings.

Referring to FIG. 5 , it is a schematic structural diagram of the solar battery sheet described in this specific embodiment. A substrate 50 is included, a first welding strip 51 and a second welding strip 52 are arranged on different surfaces of the substrate 50 respectively, and the first welding strip 51 and the second welding strip 52 are arranged symmetrically with respect to the substrate. The first welding strip 51 is electrically connected to the negative grid line of the substrate 50 , and the second welding strip 52 is electrically connected to the positive grid line of the substrate 50 . The substrate 50 further includes a through hole (not marked in the drawings), the through hole is located in the area covered by the first welding strip 51 and the second welding strip 52, and a diode chip 53 is embedded in the through hole and electrically isolated from the substrate 50 by an insulating layer 54 . The insulator filler 54 is made of an elastic material, such as any one of infrared curing glue, ultraviolet curing glue and heat curing glue, so as to ensure that the insulating layer passes between the diode chip 53 and the through hole. 54 tight fit. The cathode of the diode chip 53 is bonded to the second soldering tape 52 , and the anode of the diode chip 53 is bonded to the first soldering tape 51 . The position of the through hole is between the first soldering strip 51 and the second soldering strip 52 , which can minimize the occupation of the surface of the substrate 50 without affecting the light absorption efficiency.

The diode chip 53 refers to a chip structure including a diode structure cut directly from the wafer, and is directly used without packaging. The wafer and the substrate 50 used to make the diode chip 53 usually have similar thicknesses, so it can be ensured that the surface of the diode chip 53 shown in FIG. 5 after being embedded in the substrate 50 is flat. Because the diode chip 53 and the substrate 50 are all semiconductor materials, the reinforcement of the interface between the diode chip 53 and the two connecting pieces and the reinforcement between the substrate 50 and the two welding strips can be completed simultaneously by the same process, so there will be no increase. Additional reinforcement materials and reinforcement processes.

In other specific implementation manners, a plurality of through holes can be arranged in parallel between the first soldering strip 51 and the second soldering strip 52 to arrange a plurality of diode chips 53, so as to enhance the passability of the bypass current.

The equivalent circuit diagram of the above structure and the structural schematic diagram and equivalent circuit diagram after forming the solar cell module are similar to those of the first embodiment, so they are not described again. Similar to the previous specific embodiment, the structure provided by this specific embodiment can also ensure that when a certain solar cell fails, only the solar cell is isolated from the main circuit, while the rest of the battery string works normally. The solar cells can still generate electricity, and the diode chip is set inside the solar cell, so the volume of the whole solar cell module will not be increased.

Next, a specific implementation manner of the structure manufacturing method described in the fourth specific embodiment is given in conjunction with the accompanying drawings. Accompanying drawing 6 is a schematic diagram of the steps of this specific embodiment, including: step S60, providing a substrate, the substrate includes a positive electrode surface and a negative electrode surface; step S61, forming at least one through hole in the substrate; step S62, in The sidewall of the through hole is covered with an insulating layer; step S63, embedding a diode chip in the through hole, the positive electrode and the negative electrode of the diode chip are respectively exposed to the positive electrode surface and the negative electrode surface of the substrate; step S64, in Soldering strips are formed on the substrate surface on opposite sides of the through hole.

As shown in FIG. 7A , referring to S60 , a substrate 70 is provided, and the substrate 70 includes an anode surface and a cathode surface. The interior of the substrate 70 should include a vertical PN junction structure (not shown in the drawings) for solar cells, and the PN junction structure can be formed by any common method in the prior art. The vertical PN junction forms a P-type surface, that is, the positive electrode surface, and an N-type surface, that is, the negative electrode surface in the substrate 70 .

As shown in FIG. 7B , referring to step S61 , at least one through hole 71 is formed in the substrate 70 . The method for forming the through hole 71 may be laser ablation, plasma etching or chemical etching.

As shown in FIG. 7C , referring to step S62 , the sidewall of the through hole 71 is covered with an insulating layer 74 . The insulating layer 74 can be made of an elastic material to ensure a tight fit between the subsequently embedded diode chip and the through hole 71 through the insulating layer 74 . In order to make the bonding between the subsequently embedded diode chip and the insulating layer 74 stronger, it is preferable to use curing glue to make the insulating layer, including any one of infrared curing glue, ultraviolet curing glue and heat curing glue.

As shown in accompanying drawing 7D, referring to step S63, a diode chip 73 is embedded in the through hole 71, the anode of the diode chip 73 is exposed to the negative electrode surface of the substrate 70, and the negative electrode of the diode chip 73 is exposed to the The positive surface of the substrate 70. The diode chip 73 and the through hole 71 are tightly fitted through the insulating layer 74 .

In the embodiment where the insulating layer 74 is made by using curing glue, a step of curing the insulating layer 74 to fix the diode chip 73 should be further included after this step.

So far, the diode chip 73 has been embedded in the substrate 70 , as long as it is electrically connected to the substrate 70 , it can function as a bypass diode. There are many ways to form an electrical connection, and a direct way is to use the method of FIG. 7E and step S64 to form a first soldering strip 71 and a second soldering strip 72 on the substrate surface on opposite sides of the through hole, directly bonded to the diode chip 73 . In other specific implementation manners, a distance can also be set between the solder strip and the through hole 71 , and the two can be electrically connected through a connecting bar, and a peripheral conductive structure can also be formed.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications should also be considered Be the protection scope of the present invention.

Claims (11)

1. a solar battery sheet, comprising:

Substrate;

First assembly welding band and the second assembly welding band, described first assembly welding band comprises multiple first welding, and described second assembly welding band comprises multiple second welding, and described first welding and the second welding are arranged on the different surfaces of described substrate;

It is characterized in that, comprise at least one diode wafer further, first electrode and second electrode of described diode wafer are arranged on relative two on the surface, and the first electrode electricity of described diode wafer is connected to described first welding, the second electrode electricity of described diode wafer is connected to described second welding.

2. solar battery sheet according to claim 1, it is characterized in that, described first welding and the second welding are symmetrical arranged relative to described substrate, and described second welding has an extension, described diode wafer is be arranged between described extension and the first welding further, first electrode and described first welding of described diode wafer are fitted, and the second electrode and described second welding of described diode wafer are fitted.

3. solar battery sheet according to claim 2, is characterized in that, within the edge, extension of described second welding is positioned at described diode wafer edge.

4. solar battery sheet according to claim 1, it is characterized in that, comprise one second further and extend grid line, described second extends grid line is arranged on the surface that described substrate is provided with described second welding, and be connected with the second welding, second electrode of described diode wafer is connected to described second further by one second electrode connecting piece and extends grid line, and the first electrode of described diode wafer is connected directly to described first welding further by one first electrode connecting piece.

5. solar battery sheet according to claim 1, it is characterized in that, comprise one first further and extend grid line and one second extension grid line, described first extends grid line and second extends the different surfaces that grid line is separately positioned on described substrate, and be connected with the first welding and the second welding respectively, second electrode of described diode wafer is connected to described second further by one second electrode connecting piece and extends grid line, and the first electrode of described diode wafer is connected to described first further by one first electrode connecting piece and extends grid line.

6. solar battery sheet according to claim 1, it is characterized in that, described first welding and the second welding are symmetrical arranged relative to described substrate, and described substrate comprises a through hole further, described through hole is positioned at the region of described first welding and the covering of the second welding, described diode wafer is embedded in described through hole, and by insulating barrier and described substrate electric isolation, first electrode and described first welding of described diode wafer are fitted, and the second electrode and described second welding of described diode wafer are fitted.

7. a solar module, comprises the array be made up of multiple solar battery sheet, it is characterized in that, at least comprises the solar battery sheet described in a Claims 1 to 5 any one in described array.

8. an assemble method for bypass diode, is characterized in that, comprises the steps:

There is provided a substrate, described substrate comprises a positive electrode surface and a negative terminal surface;

At least one through hole is formed in described substrate;

Insulating barrier is covered at the sidewall of described through hole;

In described through hole, embed a diode wafer, the positive pole of described diode wafer is exposed to the negative terminal surface of described substrate, and the negative pole of described diode wafer is exposed to the positive electrode surface of described substrate.

9. the assemble method of bypass diode according to claim 7, is characterized in that, described insulating barrier adopts elastomeric material to make, and is closely cooperated between described diode wafer and described through hole by described elastomeric material.

10. the assemble method of bypass diode according to claim 7, is characterized in that, described insulating barrier adopts solidification glue to make, and after the step embedding diode wafer, comprises the described insulating barrier of solidification further with the step of fixing described diode wafer.

The assemble method of 11. bypass diodes according to claim 7, is characterized in that, the substrate surface being included in the relative both sides of described through hole further forms the step of the first welding and the second welding.