JP3619098B2 - Solar cell module - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a solar cell module, and more particularly to a solar cell module attached to a building or structure such as a roof of a house.
[0002]
[Prior art]
In recent years, when serious energy problems have been screamed, solar energy is attracting attention as one of the so-called clean energy that does not deplete like fossil energy such as oil and coal and does not destroy the environment such as air pollution and carbon dioxide generation. Collecting.
[0003]
In particular, solar power generation is expected as an alternative energy to replace conventional methods such as thermal power, nuclear power, and diesel power generation in the future.
[0004]
There are various types of materials for this solar cell, but many of those using silicon are commercially available. These are roughly divided into crystalline silicon solar cells using single crystal silicon and polycrystalline silicon, and amorphous silicon cells. It can be divided into (amorphous) silicon solar cells.
[0005]
Crystalline silicon solar cells have higher conversion efficiency, which represents the ability to convert light (solar) energy into electrical energy, compared to amorphous silicon solar cells, but the elements themselves are vulnerable to stress and are susceptible to cracking, A strong sealing structure and frame are required. In addition, there is a feature that the cost per unit power is high at present.
[0006]
On the other hand, amorphous silicon solar cells have a lower conversion efficiency than crystalline silicon solar cells at present, but have high light absorption and can form solar cells by depositing a relatively thin film, Taking advantage of the amorphous nature, various materials such as glass, stainless steel, and polyimide-based sheets can be selected as the substrate, and the area can be easily increased. Furthermore, it is said that there is a possibility that the manufacturing cost can be made relatively lower than that of the crystal system, and in the future, it is expected to spread over a wide range from the level of ordinary households to the level of large power plants.
[0007]
The solar cell modules currently on the market, excluding those used as parts such as calculators, are roughly classified into relatively small ones having a 10 cm square shape and large ones having a size of 30 cm or more.
[0008]
The small ones are for outdoor and indoor use, but the large ones are mainly intended for outdoor use, and are often installed on the ground or on the roof of buildings or on wall surfaces. In particular, when installed on the roof of a building, in many cases, it has been usual to assemble a metal base on the roof once and install and use a solar cell module on the base.
[0009]
[Problems to be solved by the invention]
However, the above-mentioned platform for installing solar cells on the roof is required to have a structure with sufficient strength for safety and to satisfy the legal regulations regarding buildings. There is a problem that the price of the main body and the installation cost are increased.
[0010]
Also, at present, there are many things that use a structure that combines a metal framework on the roof as a pedestal, but there are few things that are designed with the landscape in mind, and it will cause the local landscape to be disturbed There's a problem. In addition, when multiple solar cell modules are installed on the roof, the connection method of the wiring of each output cable outside the module is often not considered as a system, which makes the connection of the output cable complicated. There is also a problem of damaging the landscape.
[0011]
As a method for solving these problems, a method of directly attaching a solar cell to a roof material is considered. Although this method is effective in that a frame is not required, many methods require a protective cover for protecting the output cable and the output connecting member from rainwater, moisture and other external environments. However, there are few protective covers that are designed so that there is no visual discomfort with the roof.
[0012]
Furthermore, if this protective cover protrudes beyond the light receiving surface of the solar cell module, a new problem may occur due to the shade created by the protective cover.
[0013]
FIG. 7 is a plan view showing an example of a solar cell installed on a conventional roof. In the figure, reference numeral 501 denotes a maximum unit of solar cell elements connected in parallel (hereinafter referred to as a parallel solar cell element). In this conventional example, 13 parallel solar cell elements 501 are connected in series to form a solar cell panel 21. 8 solar cell panels 1 are further connected in series to form one solar cell module.
[0014]
In the figure, reference numeral 23 denotes a seam cover member (protective cover) for protecting the connection portions of these solar cell panels 21, and 30 is a shade generated by blocking incident light by the seam cover member 23. As shown in the figure, in this example, the parallel solar cell elements 501 are configured such that their longitudinal directions are arranged in a direction parallel to the longitudinal direction of the joint cover member 23 and are electrically connected in series. However, in this arrangement method, as shown in the figure, five of the parallel solar cell elements 501 are shaded, and almost no output from the parallel solar cell element 501 can be expected. As a result, not only the output current is reduced due to a decrease in the amount of incident light, but also the output voltage is reduced. For this reason, for example, when the output of the solar cell is to be directly charged to the storage battery, the output voltage does not exceed the charge voltage of the storage battery, so the output of the entire solar cell module is not charged even though it is not zero. The problem arises.
[0015]
FIG. 8 is a diagram showing a schematic configuration when a storage battery is charged by such a solar cell module. If the output of one solar cell panel 21 is 25 W and 16 V, 8 × 16 × 8 = 128V, which is a voltage sufficient to charge a 120V storage battery. However, as shown in FIG. 7 described above, when 5 of the 13 parallel solar cell elements 501 have an output of 0 V, the output of one solar cell panel 1 is 16 × (13-5) / 13 = approximately 9.85V. If this occurs for the eight solar cell panels 21, only about 9.85 × 8 = 78.8V is output where the voltage of 128V is expected, and charging of the 120V storage battery is not possible. It becomes possible.
Therefore, an object of the present invention is to prevent a reduction in output voltage by preventing the entire area of one parallel solar cell element 501 from being covered.
[0016]
[Means for Solving the Problems]
In order to solve the above-described problems, a solar cell module according to the present invention includes a plurality of rectangular plate-like members on which a solar cell panel is mounted, a joint between adjacent rectangular plate-like members, and protection of a connection portion of the solar cell. And a plurality of seam cover pressing members that press the seam cover member, and the longitudinal direction of the maximum unit of the electrically connected solar cell elements constituting the solar cell panel, The seam cover members are arranged so as to be in a direction substantially perpendicular to the longitudinal direction of the seam cover members, and the maximum units are electrically connected in series.
[0017]
The solar cell panel is characterized in that it is formed by vacuum laminating at least a surface protective material, a back surface protective material, and a solar cell element using an adhesive. Moreover, the said solar cell panel was directly fixed to the said rectangular plate-shaped member with the joining member and / or the adhesive agent, It is characterized by the above-mentioned .
[0018]
[Action]
In the solar cell module of the present invention, the longitudinal direction of the maximum unit (parallel solar cell elements) of the electrically connected solar cell elements constituting the solar cell is substantially the same as the longitudinal direction of the joint cover member. Since they are formed so as to be arranged in the vertical direction, even if shadowing is caused by the seam cover member, it is less likely to cover one entire parallel solar cell element unit.
[0019]
In addition, since the connecting portion is stored inside the joint cover member, the design is beautifully organized. Further, by integrally forming the solar cell panel by vacuum laminating, it can be easily fixed to the rectangular plate member using a bonding member such as eyelet or an adhesive.
[0020]
【Example】
Hereinafter, embodiments of the solar cell module of the present invention will be described in detail with reference to the drawings.
(Example 1)
Examples of the present invention will be described below. However, the present invention is not limited to the solar cell manufacturing method, structure, external shape, process, procedure, and roof material, structure, external shape, process, and procedure described below.
[0021]
FIG. 1 is a partial perspective view of the solar cell module of the present embodiment, in which 501 is the maximum unit (parallel solar cell device) of solar cell devices electrically connected in parallel. Further, 21 is a solar cell panel configured by connecting these parallel solar cell elements 501 in series, 22 is a rectangular plate member for placing the solar cell panel 21, and 23 is each solar cell panel. 21 is a seam cover member for protecting the connection portion 21. Reference numeral 24 denotes a seam cover pressing member, 25 denotes an eyelet as a joining member, 26 denotes an output cable, and 27 denotes an output connecting member such as a connector.
[0022]
The Figure 2 is a plan view showing an entire solar cell module of the present embodiment, the solar cell module of the present embodiment, as shown in FIG. 2, electrically connected in parallel parallel solar cell is the maximum unit Thirteen elements 501 are arranged such that the longitudinal direction thereof is substantially perpendicular to the longitudinal direction of the seam cover member 23, and the 13 elements are electrically connected in series to form one solar cell panel 21. Furthermore, eight solar cell panels 21 are electrically connected in series.
[0023]
In the present embodiment, as shown in FIG. 2 , even when the shadow 30 is generated by the joint cover member 23, the entire area of one parallel solar cell element 501 is not covered. Therefore, even if the output current of each parallel solar cell element 501 decreases, the output voltage does not decrease, and the expected output voltage can be obtained as a whole.
[0024]
As a solar cell used in this example, an amorphous solar cell element is used, and an amorphous silicon thin film is formed on a stainless steel substrate by using the RF glow discharge method, and n, i, p, n, i from the substrate side. , P in order, after vapor-depositing transparent electrodes, separating into small parts, attaching comb-shaped electrodes, electrically connecting the small parts in parallel, and a parallel solar cell element 501 having a length of about 100 mm and a width of about 300 mm did. Next, 13 pieces are arranged in the vertical direction so as to be adjacent to each other at an interval of about 1 mm, and are electrically connected in series using a copper tape to form a solar cell panel 21 as a set, and 8 sets are produced. did.
[0025]
In addition, in this embodiment, considering that the eight solar cell panels 21 are finally electrically connected in series, the element at the lower left side of the solar cell panel 21 when the solar cells are joined to the roofing material. Wiring was applied to the back surface of the solar cell panel 21 using the copper tape so that the cathode could be placed on the part where no electrode was formed and the output terminal of the anode was placed on the same part at the lower right end. At that time, polyester tape was used to insulate the stainless steel substrate and the copper tape.
[0026]
Further, as a protective material for the front and back surfaces of the solar cell panel 21, a sheet-shaped Tedlar film having a thickness of 100 μm, a length of 1500 mm and a width of 320 mm that has been previously plasma-treated, and a sheet-like EVA (ethylene -Vinyl acetate) was used for vacuum laminating at about 100 ° C. to obtain a single solar cell panel 21.
[0027]
Then, output terminals are provided at the left and right end portions of the blank portion (the portion where no element is formed) of the solar cell panel 21, and a copper cable having a cross-sectional area of 1.25 mm ² and a length of 1 m is added as the output cable 26. Each of the output terminals was soldered and the soldered portion was insulated and waterproofed using silicon rubber. At the other end of the output cable 26, an output connection member 27 was attached with a 2P waterproof connector of 100V, 15A of a male type on the plus side and a female type on the minus side. The maximum output for one solar cell panel 21 thus produced was about 25 W.
[0028]
Next, the following materials were prepared as roofing materials. First, the rectangular plate-like member 22 is made of a steel plate whose one surface is galvaluated, and has a thickness of 0.35 mm, a length of 3000 mm, and a width of about 350 mm. As shown in FIG. 4 , 8 pieces were used that were bent about 15 mm from the ends of the two opposite sides and the cross-section in the short direction was a “U”.
[0029]
The joint cover member 23 is a plate-shaped steel plate made of the same material as the rectangular plate member 22 and having a thickness of 0.35 mm, a length of 3000 mm, and a width of 90 mm, as shown in FIG. Nine pieces were used that were bent so that the “U” shape was formed, and the sides in the longitudinal direction were bent inward by about 5 mm from the end. However longitudinal ends of these members are formed in the lid-like shape as shown in FIG. 3 (a).
[0030]
The seam cover pressing member 24 is a plate steel plate having the same material as that of the rectangular plate member 22 and the seam cover member 23 and having a thickness of 0.35 mm, a length of 100 mm, and a width of 85 mm . 36 pieces each of which was folded 30 mm from both ends so as to form a “U” shape, further bent 15 mm outward, and further bent approximately 5 mm inward were used.
[0031]
Below, the joining procedure of the solar cell panel 21 and the rectangular plate-shaped member 22 is shown.
[0032]
On the surface of the prepared rectangular plate-like member 22, one solar cell panel 21 prepared in advance is provided, but the length of the parallel solar cell elements 501 having a length of about 10 cm and a width of about 30 cm connected in parallel as described above. The direction (lateral direction) is arranged so as to be substantially perpendicular to the longitudinal direction of the rectangular plate member 22, and the portion corresponding to the output cable 26 of the solar cell 21 among the bent portions of the rectangular plate member 22 As shown in FIG. 4 , a cutout 601 is provided so that each output cable 26 can pass through, and the output cable 26 is extended to the outside.
[0033]
Next, after applying a commercially available silicon-based adhesive to the surface of the back surface protective material Tedlar to adhere the solar cell panel 21 to the surface of the rectangular plate member 22, the solar cell element of the further laminated solar cell panel 21 The rectangular plate member 22 and the solar cell panel 21 were joined to each other at the four corners using eyelets 25 having a diameter of about 10 mm.
[0034]
These roofing materials and solar cells are placed on an inclined wooden plate that is 3 m long and 15 m wide, simulating the roof, and the longitudinal direction of the rectangular plate member 22 coincides with the vertical direction of the roof. Oriented and fixed so as to have an interval of 25 mm between each adjacent rectangular plate member 22. Thereafter, the seam cover pressing member 24 was arranged and fixed at a rate of about 1000 mm in the longitudinal direction of the interval portion.
[0035]
The male and female waterproof connectors as the output connection member 27 of the solar cell are arranged in the space between the adjacent rectangular plate-like members 22, and the male type and the adjacent female type and the female type and the adjacent male type are connected for series connection. Inserted the mold.
[0036]
Finally, the seam cover member 23 is fitted into the seam cover pressing member 24 from above to form a seam of a roof material, and the solar cell module of the present invention is completed. FIG. 6 is a cross-sectional view showing the configuration of the joint portion.
[0037]
The numerical values such as the above-described length and thickness of the members of the present embodiment are not particularly limited to these.
(Experimental example 1)
Using the solar cell module having the arrangement of the solar cell elements of the present invention produced in Example 1, an experiment for confirming the effectiveness of the arrangement of the parallel solar cell elements 501 of the present invention was conducted. As in Example 1, the solar cell element used in this experimental example is obtained by applying an amorphous silicon thin film on a stainless steel substrate to n, i, p, n, i, p from the substrate side using the RF glow discharge method. After sequentially depositing and vapor-depositing a transparent electrode, it is separated into small parts, comb electrodes are attached, and each small part is electrically connected in parallel to form a parallel solar cell element 501 having a length of about 100 mm and a width of 300 mm. Was used.
[0038]
In the present experimental example, the units 501 of the parallel solar cell elements are arranged so that the longitudinal direction thereof is substantially perpendicular to the longitudinal direction of the joint cover member 23 as shown in FIG. Thirteen sheets were electrically connected in series, and eight sets were prepared.
[0039]
Hereinafter, the material and procedure for vacuum lamination of the solar cell element, the materials for the output terminal, the output cable, and the waterproof connector, and the attachment were the same as those in Example 1. The output of each solar cell panel 21 was about 25W.
[0040]
This experiment was conducted in December, when the altitude of the sun is the lowest throughout the year and therefore the shadow made by the object is the longest. First, the wooden board and the solar cell module imitating the roof of Example 1 were installed on a flat ground free from obstacles in the state where the solar cell module was inclined 30 degrees with respect to the horizontal plane and the solar cell faced true south. And the output of the solar cell connected in series in Example 1 was connected to the storage battery system for 120V provided with the backflow prevention means as shown in FIG. 8 , and the voltage and electric current charged were always measured and recorded. At the same time, the degree to which the parallel solar cell elements 501 of about 10 cm in length and about 30 cm in width constituting the individual solar cell panels 21 used this time were covered by the shadow made by the joint cover member 23 was visually observed.
[0041]
As a result, it is not observed that any one of the above-mentioned parallel solar cell elements 501 is completely covered by the shadow formed by the seam cover member 23, and the output of the solar cell is drastically reduced. Was not observed, and the original purpose was achieved.
(Comparative Example 1)
As a comparative example with respect to Experimental Example 1, a solar cell module in which the arrangement of parallel solar cell elements 501 is different from the arrangement of the present invention was prototyped, and the same experiment as in Experimental Example 1 was performed. In this experiment, the longitudinal direction of the maximum unit 501 of the solar cell elements electrically connected in parallel of the individual solar cell panels 21 is arranged to coincide with the direction parallel to the longitudinal direction of the joint cover member 23.
[0042]
The parallel solar cell element 501 used in this comparative example is the same as that used in Experimental Example 1, and its longitudinal direction is parallel to the longitudinal direction of the joint cover member 23 as shown in FIG. Arrange 5 sheets, arrange 4 sheets on the side, and 4 sheets on the side, a total of 13 sheets so that the distance between them is about 1 mm. These 13 sheets are electrically connected in series. The solar cell panel 21 was prepared, and eight sets were prepared as one set.
[0043]
Hereinafter, the materials and procedures for vacuum lamination of the solar cell element, the materials for the output terminal, the output cable, and the waterproof connector, and the attachment thereof were the same as in Experimental Example 1. The output of each solar cell panel 21 was about 25W. Further, the same number of roofing materials as those in Experimental Example 1 were used.
[0044]
These roofing materials and solar cells are fixed on a wooden board simulating the same roof as in Experimental Example 1 by the same method as in Experimental Example 1, eight solar cell panels are connected in series, and finally the seam cover 23 is connected. To complete the solar cell module.
[0045]
Next, using this solar cell module, in the same manner as in Experimental Example 1, in December, a wooden board and a solar cell module simulating a roof are inclined by 30 degrees with respect to the horizontal plane, and the solar cell goes south. Installed on a flat surface with no obstacles around.
[0046]
And the output of the solar cell module produced by this comparative example was connected to the 120V storage battery system provided with the backflow prevention means shown in FIG . At the same time, the shadowing by the joint cover 23 formed on the light receiving surface of the unit 501 of each parallel solar cell element was visually observed.
[0047]
As a result, except for about two hours before and after the solar time in the sun, the shadow of the seam cover 23 is at least one or more of the parallel suns per solar panel 21 on each rectangular plate member 22. It was observed that the unit 501 of the battery element was completely covered, and correspondingly, the power charged in the storage battery was lowered and further charging was not performed.
[0048]
This is because the unit 501 of the parallel solar cell elements is completely covered with the shadow made by the seam cover member 23, so that not only the output current but also the output voltage is significantly reduced. This indicates that it has become difficult to satisfy the charging voltage.
[0049]
【The invention's effect】
As described above in detail, according to the solar cell module of the present invention, since a gantry for installing the solar cell module is not necessary, not only the gantry cost is unnecessary, but also the installation work on the roof is simplified. The safety of workers is also improved.
[0050]
In addition to the fact that the gantry is not required, the output cable and output connecting member are housed inside the roofing joint cover member, so that it is beautifully designed and eliminates the adverse effects on the local landscape. it can.
[0051]
In addition, the fact that the output cable and the output connection member are housed inside the roof joint cover member can protect the output cable and the output connection member from the external environment such as rainwater and snow, and can prevent leakage. Useful for preventing electric shocks and disconnections.
[0052]
In each solar cell, the longitudinal direction of the maximum unit (parallel solar cell element) of the electrically connected solar cell elements is arranged in a direction substantially perpendicular to the longitudinal direction of the seam cover member of the roofing material. Accordingly, it is possible to prevent the shadow produced by the seam cover member of the roof material from completely covering at least one light receiving surface of each of the parallel solar cell elements, and as a result, the output of the solar cell module is not significantly reduced.
[0053]
Furthermore, in the solar cell, at least the surface protective material, the back surface protective material, and the amorphous silicon solar cell element are vacuum-laminated using an adhesive, so that, for example, an adhesive is applied to the surface of the back surface protective material. In addition, an eyelet or the like can be used for a blank portion other than the solar cell element, and an effect of facilitating joining to the rectangular plate member can be obtained.
[0054]
In addition, this vacuum laminating process sufficiently satisfies the external environment and does not require a strong frame, reducing the solar cell production process, resulting in improved productivity and lower production costs. The effect which becomes possible is acquired.
According to the present invention, the parallel solar cells are arranged by arranging the longitudinal direction of the maximum unit of the solar cell elements electrically connected in parallel so as to be substantially perpendicular to the longitudinal direction of the joint cover member. There is an effect that the entire area of one element 501 is not covered so as to suppress a decrease in output voltage.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing an installation state of a roof material and a solar cell according to an embodiment of the present invention.
FIG. 2 is a schematic plan view of a solar cell module according to an embodiment of the present invention.
FIG. 3 is a schematic perspective view showing a cross section of a surface perpendicular to the outer shape and the longitudinal direction of a seam cover member among the roofing materials used in the examples.
FIG. 4 is a schematic perspective view showing an outer shape of a rectangular plate member among roof materials used in Examples.
FIG. 5 is a schematic perspective view showing an outer shape of a seam cover pressing member among the roofing materials used in the examples.
FIG. 6 is a schematic cross-sectional view showing the structure of each roofing material used in the examples and the connection location of each solar cell.
FIG. 7 is a schematic plan view showing a solar cell module according to a conventional arrangement.
FIG. 8 is a diagram for explaining an example of a storage battery charging system using a solar cell module.
[Explanation of symbols]
21 solar cell panel 22 rectangular plate member 23 seam cover member 24 seam cover holding member 25 joining member (grommet)
26 Output cable 27 output connection member (connector)
Largest unit of the solar cell element 28 due to the roof or structure 30 seam cover member is negative 501 electrically connected in parallel (parallel solar cell element)
601 Notch through the output cable

Claims (3)

A plurality of rectangular plate-like members on which solar cell panels are mounted, a joint cover member that protects a connecting portion of the adjacent rectangular plate-like members and a connection portion of the solar cell panel, and a plurality of seams that hold down the seam cover member A cover holding member,
The longest unit of electrically connected solar cell elements constituting the solar cell panel is arranged so as to be in a direction substantially perpendicular to the longitudinal direction of the joint cover member, and the maximum unit A solar cell module characterized in that they are electrically connected in series. The solar cell module according to claim 1, wherein the solar cell panel is configured by vacuum laminating at least a surface protective material, a back surface protective material, and a solar cell element using an adhesive. The solar cell module according to claim 1, wherein the solar cell panel is directly fixed to the rectangular plate member by a bonding member and / or an adhesive.

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