JP2000114572A - Solar battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar battery module of both side incident type in which light can be made incident from both front and rear surfaces for improving the power generating efficiency and achieving excellent design performance. SOLUTION: This is a solar battery module in which plural solar batteries 3 are sealed between a surface member 1 and a rear member 2. The solar battery 3 is constituted so that a power can be generated when lights are made incident from the both surface and rear sides, and the rear member 2 is made translucent. A terminal box 10 for outputting the power generated by the plural solar batteries 3 to the outside part is mounted to a position corresponding to the outer peripheral part of the plural solar batteries 3 on the back face side of the rear member 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell module, and more particularly to a double-sided solar cell module in which light can be incident from both the front and back sides by having a front member and a back member having translucency.

[0002]

2. Description of the Related Art A solar cell capable of directly converting the energy of light incident from the sun, which is a clean and inexhaustible energy source, into electricity is expected as a new energy source replacing fossil energy such as petroleum and coal. Is being promoted. When such a solar cell is used as an actual energy source, a solar cell module is generally used in which a plurality of solar cells are electrically connected in series or in parallel to increase the output.

A conventional solar cell module will be described with reference to FIGS. Here, FIG. 6 is a plan view, and FIG.
8 is a cross-sectional view taken along the line BB ′ in FIG. 8, and FIG. 8 is a rear view, in which a rear member described later is omitted. Also, FIG.
It is an enlarged view which shows the internal structure of a terminal box.

In these figures, reference numeral 1 denotes a front member made of a light-transmitting material such as glass or plastic, and 2 denotes a back member. The back member 2 is usually made of Al
A member having a three-layer structure having a structure in which a foil is sandwiched between resin films is used.

[0005] Reference numeral 3 denotes a solar cell.
A solar cell made of single crystal Si having a junction can be used. Here, 72 solar cells 3... 8
They are arranged in a matrix of columns × 9 rows, and are electrically connected in series by connecting members 4 made of a metal thin plate such as a copper thin plate. These solar cells 3 are sealed between the front surface member 1 and the back surface member 2 by a translucent and insulating sealing material 5 such as EVA, and the periphery thereof is easily processed with aluminum or the like. A frame 6 made of metal is attached.

The electric power generated by the solar cells 3 is led out to the terminal boxes 10, 10 provided on the back surface of the back member 2 by the power lead wires 11, 11, and the power cables (from the terminal boxes 10, 10). (Not shown).

By the way, in the mode in which a plurality of solar cells are connected in series and operated as described above, when the incident of sunlight to some of the solar cells is interrupted due to the influence of the shadow of a building, snowfall, or the like, the solar cell operates normally. The total generated voltage from the other solar cells that are generating power is applied to some of the solar cells in the form of a reverse voltage. When the reverse voltage exceeds the withstand voltage of the solar cell, the solar cell is destroyed. Alternatively, some of the solar cells generate heat, causing problems such as discoloration of EVA, foaming, or cracking of the solar cells.

In order to solve such a problem, the solar cell is usually divided into a plurality of solar cell groups, and a bypass diode is provided in parallel with the solar cell group and in the opposite direction.

For example, in the above-described solar cell module, 72 solar cells 3... Are divided into four groups of 18 solar cell groups, and a bypass diode 21 is connected to these solar cell groups by the connection wiring 12. Are connected in parallel. This bypass diode 21 is usually arranged in the terminal box 10 as shown in FIG. 9, so that the shape of the terminal box 10 is relatively large.

[0010]

By the way, in recent years, solar cells have been developed which can generate electric power by using light incident not only from the front side but also from the rear side. When a solar cell module is formed by using such a dual-incidence type solar cell, the back surface member, which has conventionally been formed using a light-impermeable member, is formed of a light-transmitting member such as glass. Light is incident on the back surface of the solar cell through the back member.

However, in the solar cell module having such a structure, light incident from the back surface side is exposed to the terminal box 1.
0, 10, power lead wires 11, 11, and connection wiring 1
2. Light is not incident on the back side of some solar cells. Therefore, the current value of some of the solar cells is only generated by light incident from the surface side, and is lower than that of other solar cells. In the solar cell module, since a plurality of solar cells are electrically connected in series, the output current of the entire module has a low current value of the above-mentioned part of the solar cells in which light does not enter the back surface side, and from the back side. The effect of light incidence becomes small.

In addition to the above-described solar cell module using a double-sided incident type solar cell, a solar cell module using a conventional solar cell may have a rear surface member made of a light-transmitting member, There is also a solar cell module in which a part of the light is transmitted to the back side to enhance the design. Even in such a solar cell module, the terminal boxes 10, 10
, Or the power lead-out lines 11, 11 or the connection wires 12,..., The amount of light transmitted to the rear surface side is reduced, and the original effect cannot be obtained.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and provides a dual-incident solar cell module capable of entering light from both front and rear sides. The solar cell module has improved power generation efficiency and excellent design. The purpose is to provide.

[0014]

To solve the above-mentioned conventional problems, a solar cell module according to the present invention is a solar cell module in which a plurality of solar cells are sealed between a front member and a back member. The solar cell is a solar cell capable of generating power by incidence of light from both sides, and the back member has translucency, and outputs electric power generated by the plurality of solar cells to the outside. A terminal box is attached at a position corresponding to the outer peripheral portions of the plurality of solar cells on the back side of the back member.

[0015] Further, the present invention is characterized in that incident light from the back side reaches the back side of the solar cell without being blocked by the terminal box.

Further, the plurality of solar cells are divided into a plurality of solar cell groups, and the terminal boxes are electrically connected in parallel in each of the solar cell groups and arranged in a straight line therein. It is characterized by having a plurality of bypass diodes.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a solar cell module according to an embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a plan view of the solar cell module according to the present embodiment, FIG. 2 is a sectional view taken along line AA ′ in FIG. 1, FIG. 3 is a rear view, and FIG. FIG. In these figures, the parts having the same functions as those in FIGS. 6 to 9 are denoted by the same reference numerals.

In the present embodiment, as the surface member 1,
Used glass having an outer dimension of 1300 mm × 875 mm.
In addition, the same size glass is used for the back surface member 2.
The module structure allows light to enter from the side. still,
The back member 2 does not need to be limited to glass, but is a transparent plastic.
A lock material or the like can also be used. Translucent like this
When using plastic materials from
Use a material with low water vapor transmission rate to improve the moisture resistance of
Preferably, the water vapor transmission rate is 20 g / m ^Two・ Da
It is preferable to use a material of y or less. Furthermore, steaming
Air permeability of 0.1 g / m^Two・ Use material less than day
Is more preferable. The value of the water vapor transmission rate is determined by JI
Measured by the Mocon method specified in SZ 0208-73
Value.

Numerals 3 are solar cells. In this embodiment, the solar cell is a double-incidence type solar cell which can generate electric power by light incident from both front and rear surfaces.

FIG. 5 is a structural sectional view showing the structure of such a dual-incidence type solar cell. In FIG. 5, reference numeral 51 denotes an n-type single-crystal silicon substrate, and a thickness of about 100
An i-type layer 52 made of intrinsic amorphous silicon of {circle around (1)} and a p-type layer 53 made of p-type amorphous silicon having a thickness of about 100 mm are laminated, and a transparent layer of ITO, ZnO, SnO ₂ or the like is formed on the p-type layer 53. A front-side translucent electrode 54 made of a photoconductive film and a front-side collecting electrode 55 made of comb-shaped metal are formed.

On the back surface of the single crystal silicon substrate 51, an i-type layer 56 made of intrinsic amorphous silicon having a thickness of about 100 ° and an n-type layer 57 made of n-type amorphous silicon having a thickness of about 100 ° are laminated. And ITO, Zn on the n-type layer 57.
A back-side light-transmitting electrode 58 made of a light-transmitting conductive film such as O and SnO ₂ and a back-side collector electrode 59 made of a comb-shaped metal are formed.

According to the solar cell having such a structure, light incident not only from the front side but also from the rear side is incident on the single-crystal silicon substrate 51, and an electron-hole pair is generated in the substrate 51. It can contribute to power generation.

Incidentally, the double-sided solar cell is not limited to a solar cell in which a crystalline semiconductor material and an amorphous semiconductor material are combined as described above, and a crystalline semiconductor material or an amorphous semiconductor material is used. It may be used alone.

In this embodiment, twelve solar cells 3 are arranged in a matrix in the row direction (vertical direction on the paper) and eight in the column direction (horizontal direction on the paper). Are electrically connected in series by a connecting member 4 made of copper foil.

The terminal box 10 is mounted on the back side of the back surface member 2 at a position corresponding to the outer periphery of the solar cells 3 arranged in a matrix, and the frame 6 is provided with fixing means such as screws or screws. It is fixed and the solar cell 3 ...
The power generated at the terminal is drawn out to the terminal box 10 by the power drawing lines 11 and 11.

Each of the 96 solar cells 3 is 2
It is divided into four groups of solar cells, each row, that is, 24 cells,
The bypass diodes 21 are electrically connected in parallel with the solar cell groups by the connection wires 12.

At this time, the lead wires 11, 11 and the connection wires 12 are arranged close to each other in the vicinity of the terminal box 10, so that it is necessary to prevent short-circuiting between the wires. It is preferable to provide an insulating film such as a PET film between them.

These bypass diodes 21 are arranged in the terminal box 10 as in the prior art. However, in the present embodiment, the bypass diodes 21 are arranged in a straight line so that the shape of the terminal box 10 is reduced. It has an elongated shape. With such an elongated shape, the terminal box 10 can be provided at a position corresponding to the peripheral portion of the solar cells 3 arranged in a matrix, so that light incident from the back surface is blocked by the terminal box 10. Without solar cell 3 ...
Can be incident on the back surface of the. Also, terminal box 1
0 is 210 mm in the case of the present embodiment.
The terminal box 10 can be as small as about 15 mm.
Can be manufactured at a lower cost than before, and the manufacturing cost of the solar cell module can be reduced.

In the present embodiment, the solar cells 3...
Are arranged in a matrix of even columns, and the bypass diodes 21 are connected for every even column (in this embodiment, every two columns).

Therefore, the power lead-out lines 11, 11 and the connecting wires 12 for connecting the bypass diodes are arranged on the same side of the solar cells 3 arranged in a matrix as shown in FIGS. Can be removed from the end. Therefore, by providing the terminal box 10 at a position corresponding to the outer peripheral portion in the row direction on the side from which these wirings 11 and 12 are taken out, the length of each of the wirings 11 and 12 can be reduced, and the cost can be reduced. In addition, it is possible to reduce the shielding of incident light from the back surface by these wirings. In addition, it is not necessary to route each of the wirings 11 and 12 in the module, so that an electrical short circuit between the connection wiring 12 and the solar cell 3 can be suppressed.

As described above, according to the solar cell module of the present invention, the terminal box is mounted on the back side of the back surface member at a position corresponding to the outer peripheral portion of the solar cell. Since the light reaches the back surface of the solar cell without being interrupted, incident light from the back surface side can also effectively contribute to power generation. In addition, since a solar cell module having a small terminal box and short wiring to the terminal box can be provided, the design is excellent.

[0033]

As described above, according to the present invention, in a dual-incidence type solar cell module capable of entering light from both sides, the power generation efficiency is improved and the solar cell module having excellent design is provided. Can be provided.

[Brief description of the drawings]

FIG. 1 is a plan view of a solar cell module according to the present invention.

FIG. 2 is a sectional view taken along line A-A 'in FIG.

FIG. 3 is a rear view of the solar cell module according to the present invention.

FIG. 4 is an explanatory diagram for explaining a structure of a terminal box according to the present invention.

FIG. 5 is a structural cross-sectional view of a dual incidence solar cell.

FIG. 6 is a plan view of a conventional solar cell module.

FIG. 7 is a sectional view taken along line B-B 'in FIG.

FIG. 8 is a rear view of a conventional solar cell module.

FIG. 9 is an explanatory diagram for explaining a structure of a conventional terminal box.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 front surface member 2 back surface member 3 solar cell 4 connection member 5 sealing material 6 frame body 10 terminal box 1
DESCRIPTION OF SYMBOLS 1 ... Power lead-out line, 12 ... Connection wiring, 21 ... Bypass diode

Claims (3)

[Claims] 1. A solar cell module in which a plurality of solar cells are sealed between a front member and a back member,
The solar cell is a solar cell capable of generating power by incidence of light from the front and back sides, and the back surface member has translucency, and a terminal box for outputting power generated by the plurality of solar cells to the outside is provided. A solar cell module attached to a position corresponding to an outer peripheral portion of the plurality of solar cells on the back side of the back surface member. 2. The solar cell module according to claim 1, wherein the incident light from the rear side reaches the rear surface of the solar cell without being blocked by the terminal box. 3. A plurality of solar cells, wherein the plurality of solar cells are divided into a plurality of solar cell groups, and wherein the terminal boxes are electrically connected in parallel for each of the solar cell groups and arranged in a straight line. The solar cell module according to claim 1, further comprising a bypass diode.