JP4302036B2 - Lighting device with solar cell and manufacturing method thereof - Google Patents

Description

  The present invention relates to an illumination device with a solar cell and a method for manufacturing the same, and more particularly to an illumination device with a solar cell in which LEDs are mounted on the back side of an integrated solar cell.

The following are known as conventional solar cell lighting devices.
A lighting device with a solar cell in which light-emitting elements are mounted around a solar cell, wiring is performed outside, and integrated with a package (see, for example, Patent Document 1).

  A substrate having an electronic circuit group on the back surface, a solar cell disposed on the front surface side of the substrate, and a light emitting element disposed on the back surface side of the substrate so as to surround the electronic circuit group. And an illuminating device with solar cell in which an electronic circuit group is electrically connected through a through hole formed in the substrate (see, for example, Patent Document 2).

A lighting device with a solar cell that disperses and arranges a plurality of light emitting elements on the back surface side of a light transmissive solar cell having a large number of slits and obtains light emission from the back surface side of the light transmissive solar cell (for example, see Non-Patent Document 1 ).
JP 2000-215704 A JP 2001-351418 A Sharp Corporation homepage, July 29, 2004 News Release “Luminous Solar Cell“ Lumiwall and Solar Street Light Newly Released ””, [online], [Search August 23, 2004], Internet <URL: http://www.sharp.co.jp/corporate/news/040729-a.html>

  In the conventional solar cell-equipped lighting device in which the light emitting element is mounted around the solar cell and wired externally, the light emitting element must be disposed on the solar cell other than the light receiving surface of the solar cell that occupies most of the exposed surface. Only the peripheral part of can be lit. Furthermore, since a housing for fixing both the light emitting element and the solar cell is required, not only the number of parts is increased and the cost is increased, but also there is a demerit that an increase in size of the apparatus cannot be avoided.

  On the other hand, in a conventional solar cell lighting device in which a solar cell, a light emitting element, and an electronic circuit group are electrically connected through a through hole formed in a substrate, a housing is unnecessary and an increase in size of the device can be avoided. Since the light emitting element is disposed only so as to surround the electronic circuit group, only the peripheral portion of the solar cell can be illuminated.

In addition, in the case where the light emitting elements are dispersed and arranged on the back side of the light transmissive solar cell, planar light emission can be obtained from the back side. The area contributing to the conversion is reduced, and it is inevitable that the photoelectric conversion efficiency is inferior to that of the non-transmissive solar cell.
In addition, since it takes time to form the slits, the manufacturing cost is inevitably high. Furthermore, since the light emitting elements can only be arranged so as to avoid the slits, there are some restrictions on the degree of freedom in arranging the light emitting elements.

  The present invention has been made in view of the above circumstances, and provides a non-transmissive solar cell-equipped lighting device capable of reducing the cost by a simple configuration while increasing the degree of freedom in arranging light emitting elements. It is to provide.

The present invention includes a non-transparent integrated solar cell including a plurality of solar cells adjacent to each other and having a front surface and a back surface, and an LED mounted on the back surface of the integrated solar cell. Provided is an illuminating device with a solar battery that has electrodes, and the positive electrode and the negative electrode of the LED are respectively mounted on the back electrodes of a pair of adjacent solar cells that are electrically separated from other solar cells that perform photoelectric conversion. Is.

According to this invention, since the positive electrode and the negative electrode of the LED are respectively mounted on the back electrodes of a pair of adjacent solar cells, the degree of freedom in disposing the LED is greatly increased, and the manufacturing process is simplified to reduce the cost. Can also be achieved.
That is, the solar cell-mounted lighting device according to the present invention uses the back electrode of some of the solar cells among the plurality of solar cells constituting the integrated solar cell as an electrode for mounting the LED. The manufacturing process is simplified while increasing the degree of freedom of arrangement.
In addition, since the integrated solar cell is non-transmissive, almost the entire area of the solar cell can contribute to photoelectric conversion, and high power generation efficiency can be obtained.

A lighting device with a solar cell according to the present invention includes a non-transmissive integrated solar cell including a plurality of solar cells adjacent to each other and having a front surface and a back surface, and an LED mounted on the back surface of the integrated solar cell, Each solar cell has a back electrode, and the positive and negative electrodes of the LED are respectively mounted on the back electrodes of a pair of adjacent solar cells that are electrically separated from other solar cells that perform photoelectric conversion. Features.

In the illumination device with a solar cell according to the present invention, the integrated solar cell is not particularly limited as long as it is a non-transmission type in which a plurality of solar cells are connected in series. Therefore, each solar cell may be either a crystalline solar cell or a thin film solar cell.
The back electrode of each solar battery cell only needs to be formed of a conductive material, and the material is not particularly limited. For example, a material made of various materials such as silver, aluminum, and an alloy of silver and aluminum can be used. .

Incidentally, in the illumination device with solar cell according to the present invention, a pair of solar cell LED are mounted, Ru is another solar cell and the electrically isolated performs photoelectric conversion.
Because solar cells and LEDs are both types of diodes having a rectifying action, a solar cell performing photoelectric conversion and a pair of solar cells mounted with LEDs are electrically connected. This is because, when the voltage is applied to the LED, the rectifying action of the solar battery cell and the rectifying action of the LED are in conflict with each other, and a state in which the solar battery does not function can occur.
A pair of solar cells mounted with L ED is not intended to photoelectric conversion, Ru exclusively used as an electrode for mounting the LED.

In the illumination device with a solar cell according to the present invention, the LED is not particularly limited as long as it has a positive electrode and a negative electrode on the same surface, and various LEDs are used from those emitting infrared light to those emitting ultraviolet light. However, it is preferable to emit visible light if used for illumination.
For example, if LEDs that emit three primary colors of RGB are regularly arranged and lighted simultaneously, it can be used as a white illumination device.
Further, if a separate control device is provided to control the light emission of the RGB LEDs, it can be used as a full-color lighting device (display body).

In the lighting device with solar cell according to the present invention, the integrated solar cell is formed on the back surface of the substrate so that the surface thereof faces the back surface of the light-transmitting insulating substrate, and a pair of solar cells on which the LEDs are mounted The cell may have an opening formed between them, and the LED may be formed with a light emitting portion so that light emission is emitted to the surface side of the insulating substrate through the opening.
According to such a configuration, the light emitted from the LED can be transmitted to the surface side of the integrated solar cell through the opening, and depending on the arrangement and the number of the LEDs, the surface side of the integrated solar cell is faced. The surface side of the integrated solar cell can be made to emit light in an arbitrary pattern if LEDs are appropriately arranged taking advantage of the degree of freedom of LED arrangement.
Examples of the method of forming the opening include various methods such as a method combining a mask pattern and etching, and laser processing.

Further, in the above structure in which light emitted from the LED is emitted to the surface side of the insulating substrate through the opening, the insulating substrate includes a translucent resin layer having a melting point of 80 to 150 ° C. on the surface side. The resin layer may have a lens formed at a position corresponding to the opening.
According to such a configuration, it is possible to effectively diffuse and collect light emitted from each LED. Further, as will be described later, the lens is formed of a resin having the same melting point of 80 to 150 ° C. as the resin for sealing the back surface side of the integrated solar cell, and therefore seals the back surface side of the integrated solar cell. It can be formed at the same time as the process, and cost can be reduced by simplifying the manufacturing process.

Further, in the above configuration in which the resin layer and the lens are formed on the front surface side of the insulating substrate, the lighting device with solar cell according to the present invention includes a translucent resin layer that seals the back surface side of the integrated solar cell, and its A back film laminated thereon is further provided, the resin layer has a melting point of 80 to 150 ° C., and the back film may have a reflectance of 80% or more with respect to visible light.
According to such a configuration, the weather resistance of the solar cell lighting device is enhanced, and the photoelectric conversion efficiency is further improved by the reflection effect of the back film.
Further, since the resin layer for sealing the back surface side has the same melting point as the resin layer formed on the front surface side of the insulating substrate, the step of forming the lens on the front surface side of the integrated solar cell and the back surface side as described above Can be simultaneously performed, and cost can be reduced by simplifying the manufacturing process.

Further, in the above configuration in which the resin layer is formed on the front surface side of the insulating substrate and the back surface side of the integrated solar cell is sealed with the resin layer, the resin layer provided on the front surface side of the insulating substrate and the integrated solar cell The resin layer for sealing the back side may be a fluororesin or EVA (ethylene-vinyl acetate copolymer).
Here, the fluororesin means a thermoplastic resin having a carbon-fluorine bond in the molecule. For example, polyvinylidene chloride (PVDC), polytetrafluoroethylene (polytetrafluoroethylene, PTFE), poly Trifluorochloroethylene (polyethylene trifluoride chloride, PTFCE), polyvinylidene fluoride (polyvinylidene fluoride, PVDF), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene / hexafluoropropylene Examples thereof include fluorine resins such as a copolymer (PFEP).

In the illumination device with a solar cell according to the present invention, the LED may have a light emitting portion so that the light emission is emitted to the back surface side of the integrated solar cell.
According to such a configuration, the back surface side of the integrated solar cell can emit light, and depending on the arrangement and number of LEDs, the back surface side of the integrated solar cell can emit light in a planar shape, and the LED arrangement If the LEDs are appropriately arranged taking advantage of this degree of freedom, the back side of the integrated solar cell can be made to emit light in an arbitrary pattern.

Further, in the above configuration in which the light emission of the LED is emitted to the back surface side of the integrated solar cell, the lighting device with a solar cell according to the present invention further includes a translucent resin layer that seals the back surface side of the integrated solar cell. The resin layer has a melting point of 80 to 150 ° C., and a lens may be formed at a position corresponding to the LED.
According to such a configuration, it is possible to effectively diffuse and collect light emitted from the LEDs. Further, since the lens is formed of a resin that seals the back surface side of the integrated solar cell, the lens can be formed by a process of sealing the back surface side of the integrated solar cell, and cost can be reduced by simplifying the manufacturing process. .

  Further, in the above configuration in which the back surface side of the integrated solar cell is sealed with the resin layer, the resin layer sealing the back surface side of the integrated solar cell may be a fluorine-based resin or EVA.

From another viewpoint, the present invention provides the above-described lighting device with a solar cell in which a resin layer and a lens are formed on the front surface side of the insulating substrate, and the back surface side of the integrated solar cell is sealed with the resin layer. A method for manufacturing, wherein a step of forming a resin layer on the front surface side of an insulating substrate and a step of sealing the back surface side of the integrated solar cell with a resin layer are performed at the same time. The present invention also provides a method for manufacturing a lighting device with a solar cell, wherein a lens is formed on a resin layer on the surface side.
According to such a manufacturing method, the process of sealing the back surface side of the integrated solar cell with the resin layer and the process of forming the resin layer on the front surface side of the insulating substrate are performed in one process, thereby the lens. Since it is formed, the manufacturing process can be simplified and the manufacturing cost can be reduced.

From another point of view, the present invention is a method for manufacturing the above solar cell illumination device in which the back surface side of the integrated solar cell is sealed with a resin layer and a lens is formed on the resin layer. In addition, the present invention also provides a method for manufacturing a solar cell-equipped lighting device, wherein a lens is formed by a step of sealing a back surface side of an integrated solar cell with a resin layer.
According to such a manufacturing method, since the lens is also formed by the process of sealing the back surface side of the integrated solar cell with the resin layer, the manufacturing process can be simplified and the manufacturing cost can be reduced.

  Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

Example 1
An illumination device with a solar cell according to Example 1 of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view showing each stage of an integrated solar cell that constitutes a lighting device with a solar cell according to Example 1, FIG. 2 is an explanatory diagram showing an equivalent circuit of the integrated solar cell shown in FIG. 1, and FIG. FIG. 4 is a perspective view showing a state in which an LED is mounted on an integrated solar cell constituting the lighting device with solar cell according to the first embodiment, and FIG. 4 is an explanation showing an equivalent circuit of the LED mounted on the integrated solar cell in the first embodiment. FIG. 5 is an explanatory diagram showing a circuit configuration of the solar cell-mounted lighting device according to the first embodiment, FIG. 6 is an explanatory diagram showing a sealing process of the integrated solar cell on which the LED is mounted in the first embodiment, and FIG. It is a principal part expanded sectional view of the illuminating device with a solar cell by Example 1. FIG.

  As shown in FIG. 3, the illuminating device with a solar cell 100 according to the first embodiment includes a non-transmissive integrated solar cell 10 having a front surface and a back surface and a plurality of solar cells 11 adjacent to each other, and an integrated type. A plurality of LEDs 20 mounted on the back surface of the solar cell 10, each solar cell 11 has a back electrode 12, and a positive electrode 21 and a negative electrode 22 (see FIG. 7) of each LED 20 are a pair of adjacent solar cells. 11 are mounted on the back electrode 12 respectively.

FIG. 1 shows one of a plurality of stages constituting the integrated solar cell 10. As shown in FIG. 1, each stage of the integrated solar cell 10 has a configuration in which a transparent electrode 14, a photoelectric conversion layer 15, and a back electrode 12 are stacked on a translucent substrate 13 (insulating substrate). Yes. The transparent electrode 14, the photoelectric conversion layer 15, and the back electrode 12 are separated into strips by a laser, and adjacent solar cells 11 are connected in series.
When such an integrated solar cell 10 is irradiated with sunlight, a current flows in the direction indicated by the arrow in the figure. FIG. 2 shows an equivalent circuit of such an integrated solar cell.

As shown in FIG. 3 and FIG. 7, the LED 20 is arranged so as to straddle the adjacent solar cells 11 in the middle stage 10 b among the upper stage 10 a, middle stage 10 b, and lower stage 10 c constituting the integrated solar cell 10. Yes.
LED20 has the positive electrode 21 and the negative electrode 22 on the same surface, and the positive electrode 21 and the negative electrode 22 are each mounted in the back surface electrode 12 of a pair of adjacent photovoltaic cell 11 of the middle stage 10b.
Since the back electrode 12 is formed of silver or an alloy of silver and aluminum, a silver paste or silver solder can be used for mounting the LED 20. In this embodiment, the back electrode 12 is mounted using silver solder. The light emitting part of the LED 20 is on the surface opposite to the surface on which the positive electrode 21 and the negative electrode 22 are formed, and emits light toward the back side of the integrated solar cell 10 (upward in FIG. 3). FIG. 4 shows an equivalent circuit of the LED 20 mounted in this way.
Accordingly, a circuit configuration as shown in FIG. 5 is realized, and the LEDs 20 can be freely arranged on the back surface of the integrated solar cell 10.

  Since the solar battery cell 11 and the LED 20 are both types of diodes having a rectifying action, the middle stage 10b on which the LED 20 is mounted has the LED 20 when a voltage is applied from the battery (see FIG. 5) to the LED 20. The solar cells 11 of the upper stage 10a and the lower stage 10c are electrically separated so that the rectification action does not conflict with the rectifying action of the solar cells 11 of the upper stage 10a and the lower stage 10c. In other words, the middle solar cell 11 is not intended for photoelectric conversion but is used as an electrode for mounting the LED 20.

As shown in FIG. 6, the integrated solar cell 10 on which the LED 20 is mounted has an EVA sheet 31, a glass plate 32, an EVA sheet 31, and a lens mold material 33 sequentially stacked on the back side in order to prevent deterioration over time. Then, it seals by performing 80-150 degreeC pressurization heat processing with a laminator, and the lens type | mold material 33 is removed after completion | finish of a sealing process. As the lens mold member 33, a film-shaped member which is formed in a lens shape and does not deform at 150 ° C. is used.
As a result, the EVA sheet 31 is embossed and deformed by the mold material during the sealing process, and as shown in FIG. 7, a minute lens 34 for light diffusion is formed on the upper part of the light emitting portion of the LED 20. Is diffused through the lens 34 and emitted to the back side of the integrated solar cell 10.

Example 2
The solar cell-equipped lighting device according to Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 8 is a perspective view showing a state in which the LED is mounted on the integrated solar cell that constitutes the solar cell lighting device according to the second embodiment, and FIG. 9 is an enlarged cross-sectional view of a main part of the solar cell lighting device according to the second embodiment. FIG. 10 is an explanatory diagram showing a sealing process of the integrated solar cell on which the LED is mounted in Example 2.

As shown in FIGS. 8 and 9, in the lighting device with solar cell 200 according to the second embodiment, the light emitting portion of each LED 50 mounted on the integrated solar cell 40 is on the same plane as the formation surface of the positive electrode 51 and the negative electrode 52. Along with this, the solar cell 41 in the middle stage 40b on which the LED 50 is mounted is one of a pair of adjacent solar cells 41 so that the light emission of each LED 50 is emitted from the surface of the translucent substrate 43. An opening 46 reaching the translucent substrate 43 is formed in the part.
The opening 46 is formed by cutting out a part of the back electrode 42, the photoelectric conversion layer 45, and the transparent electrode 44 of a pair of adjacent solar cells 41 by laser processing. The other configuration is the same as that of the integrated solar cell 10 of Example 1 (see FIG. 3).

As shown in FIG. 10, the integrated solar cell 40 on which the LED 50 is mounted has an EVA sheet 31 and a back film 35 showing a reflectance of 80% or more with respect to visible light stacked in order on the back side. The EVA sheet 31 and the lens mold material 33 are sequentially stacked on the side, and sealed by performing heat treatment at 80 to 150 ° C. with a laminator in the same manner as in Example 1. After completing the sealing process, The mold material 33 is removed.
As a result, the EVA sheet 31 on the front surface side is pressed by the mold material and deformed during the sealing process, and as shown in FIG. 9, the light diffusion microscopic area is formed above the light emitting portion of each LED 50, that is, above the opening 46. A lens 34 is formed, and light emitted from the LED 50 is diffused through the lens 34 and emitted to the surface side of the integrated solar cell 40.

In the first and second embodiments described above, the LEDs 20 and 50 are mounted on the back electrodes 12 and 42 of the pair of adjacent solar cells 11 and 41 one by one. However, the pair of adjacent solar cells 11 and 41 are adjacent to each other. It is also possible to mount a plurality of LEDs in a concentrated manner on the back electrodes 12 and 42. When a plurality of LEDs are intensively mounted, it is excellent for local lighting.
Moreover, when LED20,50 is disperse | distributed and arrange | positioned regularly like Example 1 and Example 2, uniform planar light emission is obtained and it becomes the thing excellent for an object for general illumination.
Of course, if LEDs are arranged in an arbitrary pattern taking advantage of the degree of freedom of LED arrangement, light can be emitted in a pattern corresponding thereto.

It is a perspective view which shows each step | level of the integrated solar cell which comprises the illuminating device with a solar cell by Example 1. FIG. It is explanatory drawing which shows the equivalent circuit of the integrated solar cell shown by FIG. It is a perspective view which shows the state by which LED was mounted in the integrated solar cell which comprises the illuminating device with a solar cell by Example 1. FIG. 3 is an explanatory diagram showing an equivalent circuit of an LED mounted on an integrated solar cell in Example 1. FIG. It is explanatory drawing which shows the circuit structure of the illuminating device with a solar cell by Example 1. FIG. It is explanatory drawing which shows the sealing process of the integrated solar cell by which LED was mounted in Example 1. FIG. It is a principal part expanded sectional view of the illuminating device with a solar cell by Example 1. FIG. It is a perspective view which shows the state by which LED was mounted in the integrated solar cell which comprises the illuminating device with a solar cell by Example 2. FIG. It is a principal part expanded sectional view of the illuminating device with a solar cell by Example 2. FIG. It is explanatory drawing which shows the sealing process of the integrated solar cell by which LED was mounted in Example 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10,40 ... Integrated solar cell 10a ... Upper stage 10b, 40b ... Middle stage 10c ... Lower stage 11, 41 ... Solar cell 12, 42 ... Back electrode 13, 43 ... Translucent substrate 14, 44 ... Transparent electrode 15, 45 ... Photoelectric conversion layer 20, 50 ... LED
21, 51 ... Positive electrode 22, 52 ... Negative electrode 31 ... EVA sheet 32 ... Glass plate 33 ... Lens type 34 ... Lens 35 ... Back film 46 ... Opening 100, 200 ... Lighting device with solar battery

Claims (10)

A non-transmissive integrated solar cell comprising a plurality of solar cells adjacent to each other and having a front surface and a back surface, and an LED mounted on the back surface of the integrated solar cell, each solar cell having a back electrode The positive electrode and the negative electrode of the LED are respectively mounted on the back electrodes of a pair of adjacent solar cells electrically separated from other solar cells that perform photoelectric conversion .   The integrated solar cell is formed on the back surface of the substrate so that the surface faces the back surface of the translucent insulating substrate, and the pair of solar cells on which the LEDs are mounted has an opening between them. The lighting device with a solar cell according to claim 1, wherein the LED is formed with a light emitting portion so that the emitted light is emitted to the surface side of the insulating substrate through the opening.   The solar cell according to claim 2, wherein the insulating substrate includes a translucent resin layer having a melting point of 80 to 150 ° C. on the surface side, and the resin layer has a lens formed at a position corresponding to the opening. Lighting device.   It further comprises a translucent resin layer for sealing the back side of the integrated solar cell and a back film laminated thereon, the resin layer has a melting point of 80 to 150 ° C., and the back film is visible light The solar cell-equipped lighting device according to claim 3, having a reflectance of 80% or more.   The lighting device with a solar cell according to claim 4, wherein the resin layer provided on the front surface side of the insulating substrate and the resin layer sealing the back surface side of the integrated solar cell are fluororesin or EVA.   The lighting device with a solar cell according to claim 1, wherein the LED is formed with a light emitting portion so that the emitted light is emitted to the back side of the integrated solar cell.   7. The light-transmitting resin layer for sealing the back side of the integrated solar cell is further provided, the resin layer has a melting point of 80 to 150 ° C., and a lens is formed at a position corresponding to the LED. The illuminating device with a solar cell of description.   The lighting device with a solar cell according to claim 7, wherein the resin layer that seals the back surface side of the integrated solar cell is a fluororesin or EVA.   It is a method for manufacturing the illuminating device with solar cell of Claim 4, Comprising: The process of forming a resin layer in the surface side of an insulating board | substrate, and sealing the back surface side of an integrated solar cell with a resin layer A method of manufacturing a lighting device with a solar cell, wherein the steps are performed simultaneously, whereby a lens is formed on the resin layer on the surface side of the insulating substrate.   It is a method for manufacturing the illuminating device with a solar cell of Claim 7, Comprising: A lens is formed by the process of sealing the back surface side of an integrated solar cell with a resin layer, With a solar cell Manufacturing method of lighting device.

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