TWI527254B - Solar cell module and method for manufacturing the same - Google Patents

Description

Solar battery module and method of manufacturing same

The present invention relates to a method of forming a solar cell module, and more particularly to a method of forming a solar cell module by using a conductive strip to connect a plurality of solar cell elements.

In the conventional solar cell structure, the upper electrode is disposed on the upper surface of the tantalum substrate, and the lower electrode is disposed on the lower surface of the tantalum substrate. However, the upper surface of the ruthenium substrate is used to receive the illumination of sunlight, so that the upper electrode on the upper surface shields part of the incident light, thereby reducing the photoelectric conversion efficiency of the solar cell. Therefore, the current technology has developed to move the upper electrode to the lower surface of the ruthenium substrate, so that the upper and lower electrodes (or p-type electrodes and n-type electrodes) are disposed together on the lower surface of the ruthenium substrate, and the solar cell having such a structure is called It is a back contact solar cell. Back contact solar cells can be roughly classified into four types of structures: interdigitated back contact (IBC) solar cells, emitter wrap through (EWT) back electrode solar cells, and metal penetrating (metallization wrap through, MWT) back electrode solar cells and metallization wrap around (MWA) back electrode solar cells, of which interdigitated back electrode solar cells are more common.

Please refer to the top view of the conventional interdigital back electrode solar cell 100 illustrated in FIG. 1 . As shown in FIG. 1, the conventional solar cell 100 includes an n-type diffusion region 111, a p-type diffusion region 121, an n-type bus electrode 112, a p-type bus electrode 122, a plurality of n-type finger electrodes 113, and a plurality of p-type fingers. Electrode 123. The n-type diffusion regions 111 are arranged in a comb shape, and the p-type diffusion regions 121 surround the n-type diffusion regions 111. In addition, the p-type bus electrode 122 and the plurality of p-type finger electrodes 123 are disposed on the p-type diffusion region 121 and the three are electrically connected to each other. The n-type bus electrode 112 and the plurality of n-type finger electrodes 113 are disposed on the n-type diffusion region 111 and the three are electrically connected to each other.

In addition, in the interdigitated back electrode solar cell 100, after the light is irradiated onto the upper surface of the substrate and an electron hole pair is generated, the electrons are concentrated toward the n-type diffusion region 111, and the hole is directed to the p-type diffusion region 121. Gather. However, for the pair of electron holes generated on the surface of the germanium substrate above the center of the n-type diffusion region 111, if the hole is to be moved to the distance of the p-type diffusion region 121, the electron is moved to the lower side below the n The distance of the type diffusion region 111 is relatively far. Further, for an electron hole generated on the surface of the ruthenium substrate above the center of the p-type diffusion region 121, if the electrons are moved to the distance of the n-type diffusion region 111, the hole is moved to the lower side than the hole. The distance of the type diffusion region 121 is relatively far. It is worth noting that in the n-type germanium substrate, the holes generated by the light irradiation of the substrate surface belong to a minority carrier, and the electrons belong to the majority carrier. Therefore, if the area of the n-type diffusion region 111 is too large, and the distance from the hole to the p-type diffusion region 121 is easily made too long, a minority carrier (hole) is easily lost during the movement, so that the short circuit (short circuit) Current, Isc) reduces, which in turn affects the efficiency of the solar cell. However, if the area of the n-type diffusion region 111 is reduced, the conduction resistance of most carriers will be affected. In addition, the area of the larger p-type diffusion region 121 is advantageous for collecting more minority carriers to enhance the Isc. And improve the photoelectric conversion efficiency of solar cells. However, the larger p-type diffusion region 121 causes the distance of electrons to move to the n-type diffusion region 111 to become longer. When the resistance of the electron movement becomes larger, the fill factor (FF) is lowered, thereby reducing the photoelectric conversion. effectiveness.

In order to solve the problem caused by an excessive n-type diffusion region or an excessively large p-type diffusion region under the bus electrode, the solar cell element shown in FIG. 2A is disclosed in US Pat. No. 7,804,022, and the disclosure of FIG. 2B is disclosed in US Patent No. 2005/0268959. A solar cell module of two solar cell elements.

Referring to FIG. 2A, the solar cell element 200 includes a bus electrode 202 and a finger electrode 204. The bus electrode 202 of the solar cell element 200 is reduced to a plurality of square patterns and disposed in an edge region of the solar cell element 200, compared to a bus electrode having a large area of a conventional rectangular shape. In other words, when the area of the bus electrode 202 is reduced, it means that the area of the diffusion region under the bus electrode 202 can be simultaneously reduced, so that an excessive n-type diffusion region or an excessively large p-type diffusion region under the bus electrode 202 can be solved. The problem caused. However, there is no bus electrode 202 in the intermediate portion of the above solar cell element 200. Therefore, for electrons or holes, the distance from the finger electrodes 204 to the bus electrodes 202 becomes longer. This is not conducive to the transmission of electrons or holes. In addition, since the reduced bus electrode 202 of the solar cell element 200 is disposed at the edge of the element, the finger electrodes 204 located at the edge regions of the solar cell element 200 need to be rearranged so that the finger electrodes 204 can be directly connected to the reduced Square bus electrode 202.

See also Figure 2B. Because of the special design of the above-mentioned bus electrode 202, the battery piece having the solar cell element 200a and the cell piece having the solar cell element 200b cannot be connected to each other by the conventional string welding technology, so a special design is required. The solder ribbon 206 can be realized The two cells are connected in series.

In order to solve the above disadvantages, the present invention provides a method for forming a solar cell module by connecting a plurality of solar cell elements using a conductive strip, which simplifies the process of modularizing the solar cell elements.

It is an object of the present invention to provide a method of forming a solar cell module that uses a conductive strip to connect a plurality of solar cell elements to simplify the process of modularizing the solar cell components.

Another object of the present invention is to provide a method of forming a solar cell module that uses a conductive strip to connect a plurality of solar cell elements to save the steps and costs of manufacturing the bus electrodes.

In order to achieve the above object, in one embodiment, the present invention provides a method of forming a solar cell module, comprising the steps of: providing a plurality of solar cell elements, wherein any of the solar cell elements comprises: a plurality of parallel and staggered pairs a p-type finger electrode and a plurality of n-type finger electrodes are formed on the same side surface of the solar cell element; forming a plurality of insulating pads on the plurality of p-type finger electrodes and the plurality of n-type finger electrodes; A plurality of conductive strips are electrically connected to the solar cell element in a manner perpendicular to the plurality of p-type finger electrodes and the plurality of n-type finger electrodes. The two adjacent conductive strips are electrically isolated from the plurality of p-type finger electrodes and the plurality of n-type finger electrodes by a plurality of insulating pads, respectively forming an n-type conductive strip and a p-type conductive Strips to respectively connect p-type conductive strips and n-type conductive strips of adjacent solar cell elements.

In order to achieve the above object, in another specific embodiment, the present invention further provides a method for forming a solar cell module, comprising the steps of: Providing a plurality of solar cell elements, wherein any one of the solar cell elements comprises: a plurality of p-type finger electrodes and a plurality of n-type finger electrodes arranged in parallel and staggered with each other, formed on the same side surface of the solar cell element; a plurality of insulating pads on a surface of one of the conductive strips, the plurality of insulating pads corresponding to the plurality of p-type finger electrodes or the plurality of n-type finger electrodes; and electrically connecting the plurality of conductive strips The solar cell component has a plurality of conductive strips perpendicular to the plurality of p-type finger electrodes and a plurality of n-type finger electrodes. The two adjacent conductive strips are electrically isolated from the plurality of p-type finger electrodes and the plurality of n-type finger electrodes by a plurality of insulating pads, respectively forming an n-type conductive strip and a p-type conductive Strips to respectively connect p-type conductive strips and n-type conductive strips of adjacent solar cell elements.

In order to achieve the above object, in a specific embodiment, the present invention further provides a solar cell module comprising: a plurality of solar cell elements, wherein any of the solar cell elements comprises: a plurality of p-type fingers parallel and staggered with each other An electrode and a plurality of n-type finger electrodes are formed on the same side surface of the solar cell element; a plurality of insulating pads are formed on the plurality of p-type finger electrodes and the plurality of n-type finger electrodes; and a plurality of The conductive strip is electrically connected to the solar cell element perpendicular to the plurality of p-type finger electrodes and the plurality of n-type finger electrodes; wherein the plurality of conductive strips are adjacent to each other The plurality of insulating pads are electrically isolated from the plurality of p-type finger electrodes and the plurality of n-type finger electrodes, respectively, and an n-type conductive strip and a p-type conductive strip are respectively formed to respectively connect P-type conductive strips and n-type conductive strips of adjacent solar cell elements.

100‧‧‧Solar battery components

111‧‧‧n type diffusion zone

121‧‧‧p type diffusion zone

112‧‧‧n type bus electrode

122‧‧‧p type bus electrode

113‧‧‧n type finger electrode

123‧‧‧p type finger electrode

200‧‧‧Solar battery components

200a‧‧‧Solar battery components

200b‧‧‧Solar battery components

202‧‧‧Concurrent electrode

204‧‧‧ finger electrodes

206‧‧‧ soldering tape

300‧‧‧Solar battery components

301‧‧‧p type finger electrode

302‧‧‧n type finger electrode

311‧‧‧Insulation mat

312‧‧‧Insulation mat

321‧‧‧p type conductive strip

322‧‧‧n type conductive strip

600‧‧‧Solar battery components

601‧‧‧p type finger electrode

602‧‧‧n type finger electrode

611‧‧‧Insulation mat

612‧‧‧Insulation mat

621‧‧‧p type conductive strip

622‧‧‧n type conductive strip

A-a’, b-b’‧‧‧ tangent

The above and other objects, features and advantages of the present invention will become more <RTIgt; 1 is a top view of a conventional interdigitated back electrode solar cell 100; FIG. 2A is a schematic structural view of a solar cell element disclosed in US Pat. No. 7,804,022; FIG. 2B is a disclosure of US Patent No. 2005/0268959 A solar cell module including two solar cell elements; FIG. 3A to FIG. 5B are schematic diagrams showing a method of forming a solar cell module according to an embodiment of the present invention; and FIGS. 6A to 8B are another embodiment of the present invention. A schematic flow diagram of a method of forming a solar cell module in accordance with a specific embodiment.

To illustrate the gist of the present invention, please refer to FIG. 3A to FIG. 5B , which are schematic flowcharts of a method for forming a solar cell module according to an embodiment of the present invention. 3A is a structural top view of a solar cell element according to an embodiment of the present invention; and FIG. 3B is a cross-sectional view taken along line a-a' of FIG. 3A. In FIG. 3A, the solar cell element 300 includes a plurality of p-type finger electrodes 301 and a plurality of n-type finger electrodes 302 which are parallel and staggered with each other, and are formed on the same side surface of the solar cell element, as shown in FIG. 3B. .

Preferably, the solar cell element 300 of the present embodiment is an interdigitated back electrode solar cell. However, the structure and arrangement of the interdigitated back electrode are well-known techniques and will not be described in detail in this specification.

In FIG. 4A, a plurality of insulating pads 311 and 312 are formed on a plurality of p-type finger electrodes 301 and a plurality of n-type finger electrodes 302. Figure 4B It is a cross-sectional view taken along line a-a' of Fig. 4A. In FIG. 4B, the insulating pad 311 covers the p-type finger electrode 301. Accordingly, the insulating pad 312 covers the n-type finger electrode 302. Preferably, the insulating pads 311 and 312 are formed in a printed manner.

In FIG. 5A, a plurality of conductive strips 321 and 322 are formed on the solar cell element 300 so as to be perpendicular to the plurality of p-type finger electrodes 301 and the plurality of n-type finger electrodes 302. Therefore, the adjacent two conductive strips 322 and 321 are electrically isolated from the plurality of p-type finger electrodes 301 and the plurality of n-type finger electrodes 302 by a plurality of insulating pads 311 and 312, respectively. An n-type conductive strip 322 and a p-type conductive strip 321 are respectively connected to the p-type conductive strip 321 and the n-type conductive strip 322 of the adjacent solar cell element, thereby forming a solar cell module including a plurality of solar cell elements 300 ( Not shown in the figure). Figure 5B is a cross-sectional view taken along line a-a' of Figure 5A. In FIG. 5B, the conductive strip 322 covers the insulating pad 311 to connect the n-type finger electrode 302 to become the n-type conductive strip 322. Accordingly, the conductive strip 321 covers the insulating pad 312 to connect the p-type finger electrode 301 to become the p-type conductive strip 321 .

Preferably, the conductive strips 321 and 322 are formed of a metal and welded, the metal strip is coated with a conductive plastic and formed by adhesion or heat curing, and the conductive plastic is formed by adhesion or heat curing or metal. The strip is formed with a conductive plastic and adhered by heat or heat.

The invention further provides another embodiment. Please refer to FIG. 6A to FIG. 7B , which are schematic flowcharts of a method for forming a solar cell module according to another embodiment of the present invention. 6A is a structural top view of a solar cell element according to an embodiment of the present invention; and FIG. 6B is a cross-sectional view taken along line b-b' of FIG. 6A. In FIG. 6A, the solar cell element 600 includes a plurality of p-type finger electrodes 601 and a plurality of n-type finger electrodes 602 which are parallel and staggered, and are formed on the same side of the solar cell elements. The surface is as shown in Fig. 6B.

Preferably, the solar cell element 600 of the present embodiment is an interdigitated back electrode solar cell. However, the structure and arrangement of the interdigitated back electrode are well-known techniques and will not be described in detail in this specification.

In FIG. 7A, a plurality of conductive strips 621 and 622 are provided, and a plurality of insulating pads 612 or 611 are provided on one surface of one of the conductive strips 621 or 622, and the plurality of insulating pads 612 or 611 correspond to a plurality of n-type fingers. Electrode 602 or a plurality of p-type finger electrodes 601. Figure 7B is a cross-sectional view taken along line b-b' of Figure 7A. In FIG. 7B, a plurality of insulating pads 611 are provided on one surface of the conductive strips 622, corresponding to a plurality of p-type finger electrodes 601. Accordingly, a plurality of insulating pads 612 are provided on one surface of the conductive strip 621, corresponding to the plurality of n-type finger electrodes 602. Preferably, the insulating pads 611 and 612 are formed in a printed manner.

Finally, as shown in FIG. 8A, a plurality of conductive strips 621 and 622 are attached to the solar cell element 600 such that the plurality of conductive strips 621 and 622 are perpendicular to the plurality of p-type finger electrodes 601 and a plurality of n-type fingers. Electrode 602. Therefore, the adjacent two conductive strips 622 and 621 are electrically isolated from the plurality of p-type finger electrodes 601 and the plurality of n-type finger electrodes 602 by a plurality of insulating pads 611 and 612, respectively, and respectively form a The n-type conductive strip 622 and the p-type conductive strip 621 respectively connect the p-type conductive strip 621 and the n-type conductive strip 622 of the adjacent solar cell elements, thereby forming a solar cell module including a plurality of solar cell elements 600 ( Not shown in the figure). Figure 8B is a cross-sectional view taken along line b-b' of Figure 8A. In FIG. 8B, the conductive strip 622 covers the insulating pad 611 to connect the n-type finger electrode 602 to become the n-type conductive strip 622. Accordingly, the conductive strip 621 covers the insulating pad 612 to connect the p-type finger electrode 601 to become the p-type conductive strip 621.

Preferably, the conductive strips 621 and 622 are formed of a metal and welded, the metal strip is coated with a conductive plastic and formed by adhesion or heat curing, and the conductive plastic is formed by adhesion or heat curing, or The metal strip and the conductive plastic are formed by adhesion or heat curing.

From the above description, it can be understood that the present invention uses a conductive strip to connect a plurality of solar cell elements to simplify the process of modularizing the solar cell elements. Moreover, since the bus electrodes are not connected to the finger electrodes on the solar cell elements and are directly replaced by the bus bars, the steps and costs of manufacturing the bus electrodes can be saved.

While the invention has been described above with respect to the specific embodiments thereof, it is not intended to limit the scope of the present invention, and it is possible to make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

300‧‧‧Solar battery components

301‧‧‧p type finger electrode

302‧‧‧n type finger electrode

311‧‧‧Insulation mat

312‧‧‧Insulation mat

321‧‧‧p type conductive strip

322‧‧‧n type conductive strip

A-a’‧‧‧ tangent

Claims (18)

A method of forming a solar cell module, comprising the steps of: providing a plurality of solar cell elements, wherein any of the solar cell elements comprises: a plurality of p-type finger electrodes and a plurality of n-type finger electrodes that are parallel and staggered with each other, Forming on the same side surface of the solar cell element; forming a plurality of insulating pads on the plurality of p-type finger electrodes and the plurality of n-type finger electrodes; and providing a plurality of conductive strips perpendicular to the plurality of p The finger electrode and the plurality of n-type finger electrodes are electrically connected to the solar cell component; wherein the plurality of adjacent conductive strips are respectively separated by the plurality of insulating pads Separating the plurality of p-type finger electrodes from the plurality of n-type finger electrodes to form an n-type conductive strip and a p-type conductive strip respectively to respectively connect the p-type conductive materials of the adjacent solar cell elements Strip and n-type conductive strips. The method of claim 1, wherein the plurality of insulating mats are formed in a printed manner. The method of claim 1, wherein the plurality of conductive strips are metal and are formed by soldering. The method of claim 1, wherein the plurality of conductive strips are formed by coating a conductive strip of a metal strip with a paste or heat curing. The method of claim 1, wherein the plurality of conductive strips are made of a conductive plastic and are formed by adhesion or heat curing. The method of claim 1, wherein the plurality of conductive strips are formed by metal strips and conductive plastics by adhesive or heat curing. A method of forming a solar cell module, comprising the steps of: providing a plurality of solar cell elements, wherein any of the solar cell elements comprises: a plurality of p-type finger electrodes and a plurality of n-type finger electrodes that are parallel and staggered with each other, Forming on the same side surface of the solar cell component; providing a plurality of conductive strips, wherein one of the conductive strips provides a plurality of insulating mats on a surface thereof, the plurality of insulating mats corresponding to the plurality of p-type finger electrodes or the plurality An n-type finger electrode; and electrically connecting the plurality of conductive strips to the solar cell element such that the plurality of conductive strips are perpendicular to the plurality of p-type finger electrodes and the plurality of n-type finger electrodes; The two adjacent ones of the plurality of conductive strips are electrically isolated from the plurality of p-type finger electrodes and the plurality of n-type finger electrodes by the plurality of insulating pads, respectively forming an n The conductive strip and the p-type conductive strip are respectively connected to the p-type conductive strip and the n-type conductive strip of the adjacent solar cell element. The method of claim 7, wherein the plurality of insulating mats are formed in a printed manner. The method of claim 7, wherein the plurality of conductive strips are metal and are soldered to the solar cell element. The method of claim 7, wherein the plurality of conductive strips are formed by coating a conductive strip of a metal strip with a paste or heat curing. The method of claim 7, wherein the plurality of conductive strips are conductive plastics and are attached to the solar cell element in a manner of adhesive or heat curing. The method of claim 1, wherein the plurality of conductive strips are formed by metal strips and conductive plastics by adhesive or heat curing. A solar cell module comprising: a plurality of solar cell elements, wherein any of the solar cell elements comprises: a plurality of p-type finger electrodes and a plurality of n-type finger electrodes parallel to each other and staggered, formed on the solar cell element a same side surface; a plurality of insulating pads formed on the plurality of p-type finger electrodes and the plurality of n-type finger electrodes; and a plurality of conductive strips perpendicular to the plurality of p-type finger electrodes and the a plurality of n-type finger electrodes formed to be electrically connected to the solar cell element; wherein adjacent ones of the plurality of conductive strips are respectively associated with the plurality of p-types by the plurality of insulating pads The finger electrode is electrically isolated from the plurality of n-type finger electrodes to form an n-type conductive strip and a p a type of conductive strip to connect the p-type conductive strips and the n-type conductive strips of the adjacent solar cell elements, respectively. The solar cell module of claim 13, wherein the plurality of insulating mats are formed by printing. The solar cell module of claim 13, wherein the plurality of conductive strips are metal and are formed by soldering. The solar cell module of claim 13, wherein the plurality of conductive strips are formed by coating a conductive strip of metal strips by adhesion or heat curing. The solar cell module of claim 13, wherein the plurality of conductive strips are made of conductive plastic and are formed by adhesion or heat curing. The solar cell module of claim 13, wherein the plurality of conductive strips are formed by metal strips and conductive plastics by adhesion or heat curing.