JP2009187971A - Solar battery, concentrating solar photovoltaic module, and production process of solar battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solar battery improving condensation characteristics and heat radiation properties, improving power generation efficiency and power output, and exhibiting high heat resistance, reliability and weatherability, and to provide a concentrating solar photovoltaic module and a production process of a solar battery. <P>SOLUTION: A solar battery 10 comprises a solar battery element 11 performing photoelectric conversion of sunlight Ls condensed with a condenser lens 42, a receiver substrate 20 mounting the solar battery element 11, a resin sealing portion 73 of the solar battery element 11, a columnar optical member 70 constituting a light guide for guiding the sunlight Ls condensed on an incident surface 70f to the solar battery element 11, and an optical holding portion 72 having a wall 72w for holding the columnar optical member 70 and mounted on the receiver substrate 20 to cover the resin sealing portion 73. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a solar cell that includes a solar cell element that photoelectrically converts sunlight collected by a condenser lens and a light guide that guides the collected sunlight, and a light collector that includes such a solar cell. The present invention relates to a solar photovoltaic module and a solar cell manufacturing method for manufacturing such a solar cell.

  As a solar power generation device, a non-condensing fixed type flat plate structure in which a solar power generation module configured by laying solar cell elements without gaps is installed on a roof or the like is common. On the other hand, a technique for reducing the amount of high-priced solar cell elements among members (parts) constituting the solar power generation apparatus has been proposed.

  In other words, by collecting sunlight using an optical lens or a reflecting mirror, and irradiating the collected sunlight to a small area solar cell element, the generated power per unit area of the solar cell element is increased, It has been proposed to reduce the cost of the solar cell element (that is, the cost of the solar power generation device).

  In general, the photoelectric conversion efficiency of the solar cell element is improved as the concentration factor is increased. However, if the position of the solar cell element is fixed, sunlight often enters as oblique light, and sunlight cannot be used effectively. Therefore, a tracking and concentrating solar power generation device with high condensing magnification configured to track the sun and always receive sunlight in front has been proposed (see, for example, Patent Document 1 to Patent Document 5).

  FIG. 6 is a cross-sectional view showing a configuration of a concentrating solar power generation module applied to a conventional tracking concentrating solar power generation apparatus.

  The concentrating solar power generation module 140m according to the conventional example includes a condensing lens 142 that receives and collects sunlight Lsv (sunlight Ls) incident in parallel to the optical axis Lax and perpendicular to the incident surface, A solar cell 110 that photoelectrically converts sunlight Ls (sunlight Lsa) collected by the condenser lens 142. Further, the solar cell 110 includes a solar cell element 111 that photoelectrically converts sunlight Lsa collected by the condenser lens 142 to the focal position FP, and a receiver substrate 120 on which the solar cell element 111 is placed.

  The conventional tracking concentrating solar power generation apparatus has applied the concentrating solar power generation module 140m having a high condensing magnification by the action of the condensing lens 142.

  In a tracking and concentrating solar power generation device with a high condensing magnification, in general, condensing is performed by applying a condensing lens 142. However, since the refraction by the condenser lens 142 is slightly different for each of a wide range of wavelengths included in the sunlight Ls, the wavelength region (in the sensitivity wavelength region of the solar cell element 111, particularly in the short wavelength region). Depending on the wavelength, there is a case where sunlight Ls (sunlight Lsb) that is not condensed on the solar cell element 111 is generated, which is greatly different from the normal state.

  In addition, the alignment error between the condenser lens 142 and the solar cell element 111, the positional deviation due to the difference in the temperature characteristics of the members constituting the solar power generation module 140m, and the like occur. There is a case where sunlight Ls (sunlight Lss) that is not condensed and that is misaligned in a region other than 111 is generated.

  Therefore, the sunlight Ls (sunlight Lsb, Lss) that is not condensed on the solar cell element 111 due to the difference in the refraction state depending on the wavelength region, the positional deviation between the constituent members, and the like is substantially equal to the solar cell element 111. Therefore, there is a problem in that the amount of incident light is reduced and the generated power (output) of the solar cell element 111 is reduced to cause a loss.

  Further, when the misaligned sunlight Lss is irradiated to a region other than the solar cell element 111, a member (for example, an insulating film on the receiver substrate 120, a wiring, or the like) is irradiated by the thermal energy of the misaligned sunlight Lss. ) Becomes high temperature, and in some cases, there is a problem that it may be burned out (broken).

Further, the solar cell element 111 generates heat due to the concentrated sunlight Lsa, and as a result, there is a problem that the generated power (output) decreases.
JP 2002-289896 A JP 2002-289897 A JP 2002-289898 A JP 2006-275881 A JP 2007-201109 A

  The present invention has been made in view of such a situation. A columnar optical member that irradiates solar cell elements with sunlight collected by a condensing lens without waste, and a columnar optical member placed on a receiver substrate. An object of the present invention is to provide a solar cell with high heat resistance, high reliability, and high weather resistance that has improved light-collecting characteristics and heat dissipation and improved power generation efficiency and power generation by including an optical holding unit for holding. .

  Moreover, this invention is a concentrating solar power generation module provided with the solar cell which photoelectrically converts the sunlight condensed with the condensing lens, Comprising: The solar cell which improved the condensing characteristic and heat dissipation is provided. Accordingly, another object is to provide a concentrating solar power generation module with improved heat generation efficiency and power generation and having high heat resistance, reliability, and weather resistance.

  The present invention also includes a columnar optical member that irradiates the solar cell element with sunlight collected by the condenser lens without waste, and an optical holding unit that is placed on the receiver substrate and holds the columnar optical member with a holding wall. A solar cell manufacturing method for manufacturing a solar cell comprising: a resin injection step of injecting a sealing resin that forms a resin sealing portion in a space formed by an optical holding portion (holding wall) and a receiver substrate; and a holding wall An optical member mounting step for mounting the columnar optical member, thereby positioning the optical holder and the columnar optical member with high accuracy by a simple process to improve the light collecting characteristics and heat dissipation, and to improve the power generation efficiency and power generation. Another object is to manufacture a solar cell with improved heat resistance, high reliability, and high weather resistance at low cost with high productivity.

  The solar cell according to the present invention includes a solar cell element that photoelectrically converts sunlight condensed by a condenser lens, a receiver substrate on which the solar cell element is placed, and a resin that encapsulates the solar cell element. A solar cell comprising a sealing portion, the columnar optical member constituting a light guide for guiding the concentrated sunlight to the solar cell element, and a holding wall for holding the columnar optical member And an optical holding portion placed on the receiver substrate so as to cover the resin sealing portion.

  With this configuration, it is possible to secure a light guide with high positional accuracy and stability, and to obtain a light condensing characteristic that can condense sunlight with high accuracy in a wide wavelength region. It becomes possible to obtain a solar cell with high heat resistance, high reliability, and high weather resistance in which power generation efficiency and generated power are improved by reducing power generation efficiency and temperature rise caused by misalignment of the concentrated sunlight. .

  Further, in the solar cell according to the present invention, the columnar optical member has an optical path inclined surface for collecting sunlight on the solar cell element, and the holding wall is a holding inclined surface aligned with the optical path inclined surface. It is characterized by being.

  With this configuration, the columnar optical member can be aligned with the optical holding portion in a self-aligning manner, and the columnar optical member can be held with high accuracy by the holding wall, so that the light guide path is positioned with high accuracy. In addition, the light condensing characteristics can be improved.

  In the solar cell according to the present invention, the optical holding portion is in contact with a metal base base included in the receiver substrate.

  With this configuration, it is possible to reduce the thermal resistance between the receiver substrate and the optical holder, and to efficiently dissipate the heat conducted from the solar cell element to the receiver substrate, thereby improving power generation efficiency and reliability. Can be improved.

  Moreover, in the solar cell according to the present invention, the optical holding portion includes comb-shaped fins on an outer peripheral side surface.

  With this configuration, the heat dissipation characteristics can be further improved, and the power generation efficiency and reliability can be further improved.

  Moreover, in the solar cell according to the present invention, the columnar optical member is a quadrangular column, and the optical holding unit includes a groove-shaped notch that surrounds an axial corner of the quadrangular column. To do.

  With this configuration, it is possible to prevent damage by the optical holding portion at the corners in the axial direction of the columnar optical member, and it is possible to place the columnar optical member on the optical holding portion reliably and with high accuracy. Since the defoaming and filling of the sealing resin filled between the member and the optical holding unit can be performed reliably, the light guide path can be defined (positioned) with high accuracy.

  Moreover, in the solar cell which concerns on this invention, the said resin sealing part is made thinner than the surrounding area between the said columnar optical member and the said solar cell element, It is characterized by the above-mentioned.

  With this configuration, the surface (irradiation surface) facing the solar cell element of the columnar optical member can be reliably brought close to the solar cell element, so that the sunlight collected by the columnar optical member is effectively collected. The solar cell element can be irradiated. Moreover, since it becomes possible to suppress the temperature rise of the receiver board | substrate in a surrounding area, it can be set as a solar cell with improved heat resistance and high reliability and a weather resistance.

  Moreover, the concentrating solar power generation module according to the present invention includes a concentrating solar comprising a condensing lens that condenses sunlight and a solar cell that photoelectrically converts the sunlight condensed by the condensing lens. A photovoltaic module, wherein the solar cell is a solar cell according to the present invention.

  With this configuration, it is possible to secure a light guide with high positional accuracy and stability, and to obtain a light condensing characteristic that can condense sunlight with high accuracy in a wide wavelength region. A concentrated solar photovoltaic module with high heat resistance, reliability, and weather resistance that improves power generation efficiency and power generation by reducing power generation efficiency and temperature rise caused by misalignment of the concentrated sunlight. It becomes possible.

  The solar cell manufacturing method according to the present invention includes a solar cell element that photoelectrically converts sunlight condensed by a condenser lens, a receiver substrate on which the solar cell element is placed, and the solar cell element as a resin. A resin sealing portion that seals, a columnar optical member that constitutes a light guide path that guides the concentrated sunlight to the solar cell element, and a holding wall that holds the columnar optical member; A solar cell manufacturing method for manufacturing a solar cell including an optical holding unit placed on the receiver substrate so as to cover a part, and forming an optical holding unit by forming a metal to prepare the optical holding unit; An optical holding part arranging step of placing the optical holding part in contact with the receiver substrate on an outer periphery of the solar cell element, and forming the resin sealing part in a space formed by the optical holding part and the receiver substrate Inject sealing resin A resin injection step, characterized in that it comprises an optical member placement step of placing the columnar optical member on the holding wall.

  With this configuration, the optical holding unit and the columnar optical member can be positioned with high accuracy by a simple process, and a light guide and an optical holding unit for effectively guiding sunlight with high accuracy can be easily formed. Therefore, heat collection characteristics and heat dissipation are improved, heat generation efficiency and power generation efficiency are improved by reducing power generation efficiency and preventing temperature rise caused by misalignment of the concentrated sunlight. Therefore, it becomes possible to manufacture a solar cell having high weather resistance at low cost with good productivity.

  According to the solar cell of the present invention, a solar cell element that photoelectrically converts sunlight collected by the condenser lens, a receiver substrate on which the solar cell element is placed, and a resin that encapsulates the solar cell element A columnar optical member that constitutes a light guide path that guides the collected sunlight to the solar cell element, and a holding wall that holds the columnar optical member and covers the resin sealing unit. Since the optical holding unit placed on the substrate is provided, a light collecting path with high positional accuracy and stability can be secured to obtain a light collecting characteristic capable of collecting sunlight with high accuracy in a wide wavelength region. Improved heat characteristics, improved heat resistance, improved heat generation efficiency and power generation by improving light characteristics and heat dissipation, preventing power generation efficiency reduction and temperature rise caused by misalignment of concentrated sunlight There is an effect that can be

  The concentrating solar power generation module according to the present invention includes a condensing lens that condenses sunlight, and a solar cell that photoelectrically converts the sunlight collected by the condensing lens. Is a solar cell according to the present invention, so that a light condensing characteristic capable of concentrating sunlight with high accuracy in a wide wavelength region by securing a light guide having high positional accuracy and stability is obtained. And improve heat dissipation, improve heat generation efficiency and power generation, reduce heat generation efficiency and prevent temperature rise caused by misalignment of the concentrated sunlight, and improve heat resistance, reliability, and weather resistance There is an effect that can be.

  According to the solar cell manufacturing method of the present invention, a solar cell element that photoelectrically converts sunlight collected by the condenser lens, a receiver substrate on which the solar cell element is placed, and the solar cell element are resin-sealed A resin sealing portion, a columnar optical member that constitutes a light guide for guiding the condensed sunlight to the solar cell element, and a holding wall that holds the columnar optical member, covering the resin sealing portion, and a receiver A solar cell manufacturing method for manufacturing a solar cell including an optical holding unit placed on a substrate, wherein an optical holding unit preparing step of preparing an optical holding unit by molding a metal, and the optical holding unit as a solar cell An optical holder placement step for placing the optical holder in contact with the receiver substrate at the outer periphery of the element, a resin injection step for injecting a sealing resin to form a resin sealing portion in the space formed by the optical holder and the receiver substrate, and holding Place the columnar optical member on the wall It is possible to position the optical holding part and the columnar optical member with high accuracy in a simple process, and to guide the sunlight effectively with high accuracy. Can be formed easily, improving the light collection efficiency and heat dissipation, and improving the power generation efficiency and power generation by reducing the power generation efficiency and preventing the temperature rise caused by the misalignment of the concentrated sunlight Thus, it is possible to produce a solar cell having high heat resistance, reliability, and weather resistance with high productivity and low cost.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Embodiment 1>
A solar cell and a concentrating solar power generation module according to the present embodiment will be described with reference to FIGS.

  1 is a cross-sectional view showing a solar cell and a concentrating solar power generation module according to Embodiment 1 of the present invention. FIG. 2 is an enlarged plan view showing a state in which the solar cell shown in FIG. 1 is enlarged from the condenser lens side. FIG. 3 is an enlarged cross-sectional view showing a cross section in the direction of arrows Y-Y in FIG. Note that the cross-sectional view of the solar cell in FIG. 1 is a cross-section in the direction of arrows XX in FIG.

  In solar cell 10 according to the present embodiment, solar cell element 11 that photoelectrically converts sunlight Ls (sunlight Lsa, sunlight Lsb) collected by condenser lens 42 and solar cell element 11 are placed. It is the solar cell 10 provided with the receiver board | substrate 20 and the resin sealing part 73 which resin-seal the solar cell element 11. FIG.

  The sunlight Lsa is sunlight that is normally condensed by the condenser lens 42 and directly incident on the solar cell element 11. Further, the sunlight Lsb is condensed by the condenser lens 42, but cannot be directly incident on the solar cell element 11 due to the influence of the lens end portion, the wavelength region (particularly, the short wavelength region), and the like. It is the sunlight that travels while being reflected inside the light guide path (columnar optical member 70) and is applied to the solar cell element 11 by being condensed on the incident surface 70f (condensing region Af) of the optical member 70. . That is, the sunlight Lsb is sunlight that has been a loss in the prior art.

  Further, the solar cell 10 includes a columnar optical member 70 that constitutes a light guide path that guides the concentrated sunlight Ls to the solar cell element 11, and a holding wall 72w that holds the columnar optical member 70. And an optical holding part 72 placed on the receiver substrate 20 so as to cover the part 73.

  Therefore, a light collecting path (columnar optical member 70) having high positional accuracy and stability is obtained, and a light collecting characteristic capable of collecting sunlight Ls with high accuracy in a wide wavelength region is obtained. The solar cell 10 having high heat resistance, high reliability, and high weather resistance, which improves power generation efficiency and power generation power by reducing the power generation efficiency and preventing temperature rise caused by the positional deviation of the concentrated sunlight Ls. It becomes possible.

  The receiver substrate 20 is connected to a desired wiring (electrode (not shown) of the solar cell element 11) via an appropriate insulating layer on a metal base base such as an aluminum plate or a copper plate, and is connected to the outside. In addition, a connection pattern (not shown) for connecting the solar cells 10 in series or in parallel is formed.

  That is, the current generated by the solar cell element 11 is appropriately extracted to the outside of the solar cell 10 by the wiring formed on the receiver substrate 20. Since the wiring formed on the receiver substrate 20 needs to ensure highly reliable insulation, for example, a connection pattern formed of copper foil is insulated by covering it with an insulating film such as an organic material. is there.

  Further, the columnar optical member 70 has an optical path inclined surface 70s for condensing sunlight Ls on the solar cell element 11, and the holding wall 72w is a holding inclined surface aligned with the optical path inclined surface 70s.

  Therefore, the columnar optical member 70 can be aligned with the optical holding portion 72 in a self-aligning manner, and the columnar optical member 70 can be held with high accuracy by the holding wall 72w. The member 70) can be positioned with high accuracy, and the light collecting characteristics can be improved.

  The columnar optical member 70 is made of, for example, heat resistant glass and has a refractive index of about 1.5, for example. The width of the incident surface 70f (condensing region Af) of the columnar optical member 70 on which the sunlight Ls is condensed is the short wavelength light most refracted among the sunlight Lsb refracted at the end of the condenser lens 42. The size is such that about 400 nm of sunlight can be incident.

  Moreover, the irradiation surface 70r of the light guide (columnar optical member 70) on which the solar light Ls is irradiated to the solar cell element 11 is an effective light receiving surface region of the solar cell element 11 so that the irradiation to the solar cell 10 can be performed efficiently. It is formed in the same size as. Accordingly, the columnar optical member 70 includes an optical path inclined surface 70s that tapers from the incident surface 70f to the irradiation surface 70r.

  The angle of the optical holding part 72 (holding wall 72w) with respect to the receiver substrate 20 is 45 ° or more, and the incident solar light Lsb is totally reflected, so that the solar cell element 11 can be irradiated. Further, the height Hp of the columnar optical member 70 from the receiver substrate 20 is the angle of the inclined surface of the optical holding portion 72, the size of the area of the irradiation surface 70r corresponding to the area of the solar cell element 11 (effective light receiving surface region), It can be determined by the size of the incident surface 70 f of the columnar optical member 70.

  Therefore, the size of the columnar optical member 70 is the area of the incident surface 70f on which the sunlight Ls is incident without loss, the holding wall 72w (holding slope) of the optical holder 72 that totally reflects the sunlight Ls and irradiates the solar cell element 11. Surface) from the receiver substrate 20 and the area of the irradiation surface 70r.

  Further, when total reflection at the columnar optical member 70 cannot be used due to the relationship with the optical holding unit 72, a metal film such as Al, Ag, or Ni is vacuum-deposited or sputtered on the optical path inclined surface 70s of the columnar optical member 70. You may provide the reflective surface formed by the above.

  As described above, the columnar optical member 70 according to the present embodiment causes the sunlight Lsa normally collected by the condenser lens 42 to be directly incident on the solar cell element 11 and collected on the incident surface 70f by the condenser lens 42. The sunlight Lsb that has been emitted can be allowed to travel while being reflected by the light guide path (columnar optical member 70) and incident on the solar cell element 11, and the power generation efficiency of the solar cell 10 can be increased.

  The optical holding unit 72 is brought into contact with a metal base (not shown) of the receiver substrate 20 and is bonded to the receiver substrate 20 by the bonding unit 21. That is, the optical holding part 72 is directly bonded to the receiver substrate 20 (base base) in a state where an appropriate contact area is secured.

  Therefore, heat generated in the receiver substrate 20 (solar cell element 11) due to the concentrated sunlight Ls can be efficiently conducted to the optical holding unit 72 formed of metal, and the optical holding unit Since the heat conducted to 72 is effectively radiated by the fins 72h having an increased heat radiation area, it is possible to efficiently radiate the heat caused by the sunlight Ls collected on the solar cell element 11, The power generation efficiency and reliability of the solar cell 10 can be improved.

  Note that the optical holding portion 72 is preferably formed of, for example, metal. By forming it with metal, the optical holding part 72 having excellent heat dissipation can be easily and inexpensively formed with good mass productivity.

  The optical holding unit 72 includes, for example, comb-shaped fins 72h on the outer peripheral side surface. Therefore, it is possible to further improve the heat dissipation characteristics, and it is possible to further improve the power generation efficiency and reliability. The fin 72h has a shape that is inclined in the direction away from the receiver substrate 20 from the base to the tip (upward), and further improves heat dissipation.

  The columnar optical member 70 is a quadrangular column, and the optical holding unit 72 includes a groove-shaped notch 72g that surrounds the axial corner 70c of the quadrangular column. Therefore, it is possible to prevent the optical holding portion 72 from being damaged at the axial corner portion 70 c of the columnar optical member 70, and to place the columnar optical member 70 on the optical holding portion 72 reliably and with high accuracy.

  Further, the notched portion 72g can surely degas and fill the sealing resin 73r (see FIG. 4C) filled between the columnar optical member 70 and the optical holding portion 72. The optical path (columnar optical member 70) is defined (positioned) with high accuracy, and a high-quality light guide path in which bubbles are not mixed between the optical path inclined surface 70s and the holding wall 72w or in the resin sealing portion 73 is obtained. be able to.

  The optical holding portion 72 is preferably formed such that the height Hh from the receiver substrate 20 is higher than the center of gravity position Wb of the columnar optical member 70. With this configuration, the center of gravity of the columnar optical member 70 can be reliably and reliably held by the optical holding portion 72. Therefore, it is possible to prevent the columnar optical member 70 from shaking or falling by the optical holding portion 72, and to suppress the shaking of the concentrated sunlight Ls and to perform highly reliable power generation, thereby improving the reliability of the solar cell 10. Can be improved.

  Further, by interposing the sealing resin 73r, the columnar optical member 70 can be brought into close contact with the optical holding portion 72, and the columnar optical member 70 can be stably placed on the optical holding portion 72. Since it becomes possible, productivity can be improved.

  The resin sealing portion 73 is composed of an insulating sealing resin 73r filled between the solar cell element 11 and the optical holding portion 72. For example, by applying a transparent silicone resin, a columnar optical member is formed. The solar cell element 11 can be irradiated with sunlight Ls that has passed through 70.

  The resin sealing portion 73 is thinner than the surrounding region between the columnar optical member 70 and the solar cell element 11. That is, the thickness Tr in the surrounding region is formed to be thicker than the thickness Ts between the columnar optical member 70 and the solar cell element 11.

  Therefore, since the surface (irradiation surface 70r) facing the solar cell element 11 of the columnar optical member 70 can be surely brought close to the solar cell element 11 (effective light receiving surface region), the columnar optical member 70 collects the columnar optical member 70. The illuminated sunlight Ls can be effectively applied to the solar cell element 11.

  Moreover, since it becomes possible to suppress the temperature rise of the receiver board | substrate 20 in the surrounding area | region of the solar cell element 11, heat resistance can be improved and it can be set as the solar cell 10 with high reliability and weather resistance.

  The sunlight Ls is configured to be collected on the solar cell element 11 by the tracking mechanism. For example, the sunlight Ls may be misaligned due to the occurrence of a tracking error or an alignment error of the optical system. That is, the solar cell 10 may be irradiated with the misaligned sunlight Lss. In the following, the deviation of the focused spot due to tracking error, alignment error, variation in light intensity, etc. may be described simply as tracking error (such as tracking error).

  The optical holding part 72 is a condensing region Af (columnar optical member 70) set for sunlight Ls (sunlight Lsa, sunlight Lsb) collected toward the solar cell element 11 (effective light receiving surface region). ), The sunlight Lss can be reflected when the sunlight Lss is generated.

  Therefore, even when the concentrated sunlight Ls is displaced due to, for example, a tracking error, and the sunlight Lss irradiates a position shifted from the position of the solar cell element 11 (effective light receiving surface region), Irradiation of sunlight Lss to the receiver substrate 20 can be prevented.

  As described above, the wiring formed on the surface of the receiver substrate 20 is composed of an organic member having low heat resistance. Therefore, if sunlight Lss is irradiated, the organic member is damaged, and thus the wiring is damaged. And the reliability of the solar cell 10 may be reduced. However, since the receiver substrate 20 around the solar cell element 11 is covered by the optical holding portion 72 (and the resin sealing portion 73), the sunlight Lss is directly irradiated onto the receiver substrate 20 (wiring). Therefore, it is possible to prevent damage to the wiring and the like, so that the temperature rise on the surface of the receiver substrate 20 is suppressed, and the members (wiring, insulating film, etc.) disposed on the surface of the receiver substrate 20 are burned out. Can be prevented.

That is, by disposing the optical holder 72 on the receiver substrate 20 in the outer peripheral region of the solar cell element 11, the wiring (organic member) of the receiver substrate 20 can be obtained even in the case of a high condensing magnification of 600 SUN (1 SUN = 100 mW / cm ² ) or more. ) And the like, and it is possible to obtain a highly efficient and inexpensive solar cell 10 with improved heat resistance, good reliability and weather resistance.

  Moreover, as above-mentioned, the optical holding | maintenance part 72 can reflect sunlight Lss effectively by using, for example as a metal.

  The solar cell element 11 is made of an inorganic material such as Si, GaAs, CuInGaSe, CdTe, for example. Further, the solar cell element 11 has various structures such as a single junction solar cell element, a monolithic multi-junction solar cell element, and a mechanical stack type in which various solar cell solar cell elements having different wavelength sensitivity regions are connected. It is possible to apply.

  Note that the outer size of the solar cell element 11 is preferably about several mm to about 20 mm from the viewpoints of reduction of solar cell materials to be used, ease of processing, ease of process, simplification, and the like.

  In order to reduce the light reflectance in the sensitivity wavelength region of the solar cell element 11, an appropriate antireflection film or the like may be provided on the surface of the solar cell element 11. Furthermore, a UV reflection film, an infrared reflection film, or the like that reflects sunlight having a wavelength other than the sensitivity wavelength region of the solar cell element 11 may be provided.

  The concentrating solar power generation module 40m according to the present embodiment includes a condensing lens 42 that condenses sunlight Ls (sunlight Lsv), and sunlight Ls (sunlight Lsa) collected by the condensing lens 42. The solar cell 10 (solar cell element 11) that photoelectrically converts sunlight Lsb).

  The condensing lens 42 is configured to face the sun by the action of a tracking mechanism (not shown). Therefore, the sunlight Lsv is incident in a direction perpendicular to the incident surface of the condenser lens 42. The condensing lens 42 is configured to refract the sunlight Lsv and condense it on the solar cell element 11 (in this embodiment, the incident surface 70f as the condensing region Af).

  In the solar cell 10, a light collecting characteristic capable of concentrating sunlight Ls in a wide wavelength region including a wavelength in a short wavelength region with high accuracy by securing a light guide (columnar optical member 70) having high positional accuracy and stability. Therefore, it is possible to improve the heat collecting property by improving the condensing characteristics and reducing the power generating efficiency and preventing the temperature rise caused by the positional deviation of the concentrated sunlight Ls. In addition, it is possible to obtain a concentrating solar power generation module 40m with improved reliability and high weather resistance with improved generated power.

  The solar cell element 11 applied to the concentrating solar power generation module 40m is particularly required to have high efficiency and practicality. Therefore, a three-junction solar cell element composed of InGaP / GaAs / Ge, AlGaAs / It is desirable to use a solar cell element made of Si or a monolithic multi-junction solar cell element.

  In order to effectively collect light by the condensing lens 42, the surface of the solar cell element 11 that photoelectrically converts sunlight Ls is flat, the incident surface of the condensing lens 42, the incident surface 70f of the columnar optical member 70, irradiation It is arranged parallel to the surface 70r.

  Examples of the condenser lens 42 include a biconvex lens, a plano-convex lens, and a Fresnel lens. From the viewpoint of weight, cost, ease of handling in the usage environment, etc., the Fresnel lens has a flat entrance surface for receiving sunlight Ls and an exit surface for irradiating solar cell element 11 with sunlight Ls having a substantially triangular cross section. It is desirable to have a shape. In addition, the condensing lens 42 can also be made into the array form (refer FIG. 5) which shape | molded and integrated the same optical system.

  As a material of the condensing lens 42, the thing with the high transmittance | permeability with the sensitivity wavelength light of the solar cell element 11 and a weather resistance is good. For example, it is possible to apply a thin glass generally used for a normal solar cell module (solar power generation system), weather resistant grade acrylic, polycarbonate, or the like. In addition, the material of the condensing lens 42 is not limited to these, You may make these materials into the multilayer structure. In addition, an appropriate ultraviolet absorber can be added to these materials for the purpose of preventing ultraviolet degradation of the condenser lens 42 itself and other members.

<Embodiment 2>
Based on FIG. 4A thru | or FIG. 4D, the solar cell manufacturing method which concerns on this Embodiment is demonstrated. In addition, since the solar cell manufactured with the solar cell manufacturing method which concerns on this Embodiment is the solar cell 10 which concerns on Embodiment 1, the code | symbol in Embodiment 1 is applied as it is.

  Apart from the process of FIG. 4A (solar cell element mounting process), first, the metal is molded to prepare the optical holding part 72 (optical holding part preparing process). Note that the shape of the optical holding portion 72 is as described in the first embodiment, and thus the description thereof is omitted as appropriate.

  That is, the holding wall 72w (holding inclined surface) having the same inclination angle as the optical path inclined surface 70s corresponding to the optical path inclined surface 70s of the columnar optical member 70 is formed inside the metal block. In addition, a notch 72g is formed corresponding to the axial corner 70c of the columnar optical member 70. In addition, a space that covers the resin sealing portion 73 is formed adjacent to the surface that contacts the receiver substrate 20. Further, the fin 72 h is formed on the outer periphery of the optical holding portion 72.

  In addition, as a manufacturing method of the optical holding | maintenance part 72, there exists the die casting method which can process with high precision, or the method of cutting and manufacturing a metal block.

  FIG. 4A is a process diagram for explaining a solar cell manufacturing method according to Embodiment 2 of the present invention, and shows a state in which a solar cell element is placed on a receiver substrate in a cross section in the direction of arrows XX in FIG. Show.

  Separately from the optical holder preparation step, the solar cell element 11 is mounted on the receiver substrate 20 (solar cell element mounting step).

  FIG. 4B is a process diagram for explaining the solar cell manufacturing method according to Embodiment 2 of the present invention, and shows a state in which the optical holding unit is placed on the receiver substrate in a cross section in the direction of arrows XX in FIG. Show.

  After mounting the solar cell element 11 on the receiver substrate 20, the bonding portion 21 is formed on the receiver substrate 20 in correspondence with the position where the optical holding portion 72 is disposed on the outer periphery of the solar cell element 11 (bonding portion forming step). For example, a metal frame or a plastic frame can be formed and disposed as the bonding portion 21, but it is desirable to appropriately arrange a resin or an adhesive that can bond the optical holding portion 72.

  The bonding unit 21 bonds the optical holding unit 72 to the receiver substrate 20 on the side surface of the optical holding unit 72 so that the optical holding unit 72 can be brought into direct contact with a base base (not shown) of the receiver substrate 20. Placed in. In the case where an adhesive having high thermal conductivity is applied, the adhesive portion 21 may be inserted between the receiver substrate 20 and the optical holding portion 72.

  After forming the bonding part 21, the optical holding part 72 is placed in contact with the receiver substrate 20 in alignment with the bonding part 21 (optical holding part arranging step). At this time, the optical holder 72 is mounted so that the center position of the optical holder 72 (corresponding to the center position of the irradiation surface 70r) formed by the holding wall 72w and the center of the solar cell element 11 (effective light receiving surface area) are aligned. Put.

  FIG. 4C is a process diagram for explaining the solar cell manufacturing method according to Embodiment 2 of the present invention, in which the sealing resin is injected into the space formed between the optical holder and the receiver substrate in FIG. Shown in cross section in the direction of arrow XX.

  Through the space formed by the holding wall 72w, to the space formed by the optical holding portion 72 and the receiver substrate 20 (the space forming the resin sealing portion 73 and part of the space where the columnar optical member 70 is disposed). A sealing resin 73r for protecting the element 11 is injected (resin injection step).

  The injection amount of the sealing resin 73r is such that when the columnar optical member 70 is placed, the sealing resin 73r fills the gap between the columnar optical member 70 and the optical holding portion 72, and the optical holding portion 72 (notch portion) 72 g), and an appropriate amount obtained in advance is injected.

  FIG. 4D is a process diagram illustrating the solar cell manufacturing method according to Embodiment 2 of the present invention, and shows a state in which the columnar optical member is placed on the optical holding portion in the direction of arrows XX in FIG. It shows with.

  Before the injected sealing resin 73r is cured, the columnar optical member 70 is placed on the optical holding portion 72 (holding wall 72w) (optical member placement step), and is stored in a vacuum chamber for defoaming (bubbles) Defoaming step). Since the cutout portion 72g formed in the optical holding portion 72 serves as a bubble discharge path, reliable defoaming can be performed by a simple process.

  Since the pressure of the sealing resin 73r is reduced by performing defoaming in the bubble defoaming step, the columnar optical member 70 is pressed against the holding wall 72w by its own weight and is self-aligned to the solar cell element 11 side with high accuracy. Inserted. Further, since the sealing resin 73r is filled between the columnar optical member 70 and the optical holding portion 72 and acts as a lubricant, the frictional resistance between the columnar optical member 70 and the optical holding portion 72 is reduced. While protecting the surface of the columnar optical member 70, it becomes possible to mount (couple) the optical holding unit 72 more smoothly.

  After the bubble defoaming step, the sealing resin 73r is hardened to form the resin sealing portion 73, and the columnar optical member 70 and the optical holding portion 72 are adhered and fixed (resin curing step / columnar optical member fixing step). ).

  As described above, in the solar cell manufacturing method according to the present embodiment, the solar cell element 11 that photoelectrically converts the sunlight Ls collected by the condenser lens 42 and the receiver substrate 20 on which the solar cell element 11 is placed. A resin sealing portion 73 for resin-sealing the solar cell element 11, a columnar optical member 70 that constitutes a light guide for guiding the concentrated sunlight Ls to the solar cell element 11, and a columnar optical member 70. The present invention relates to a solar cell manufacturing method for manufacturing a solar cell 10 that includes a holding wall 72 w to hold and an optical holding portion 72 that covers a resin sealing portion 73 and is placed on a receiver substrate 20.

  In addition, the solar cell manufacturing method according to the present embodiment includes an optical holding unit preparing step of forming a metal to prepare the optical holding unit 72, and the optical holding unit 72 on the receiver substrate 20 on the outer periphery of the solar cell element 11. An optical holding part placement step for placing the resin in contact with each other, a resin injection step for injecting a sealing resin 73r for forming the resin sealing portion 73 into the space formed by the optical holding part 72 and the receiver substrate 20, and a holding wall 72w An optical member placing step for placing the columnar optical member 70.

  Therefore, the optical holding part 72 and the columnar optical member 70 can be positioned with high accuracy by a simple process, and the light guide (columnar optical member 70) and the optical holding for effectively guiding the sunlight Ls with high accuracy. Since the portion 72 can be easily formed, the light collection efficiency and the generated power are improved by improving the light collecting characteristics and heat dissipation, and preventing the power generation efficiency from being reduced and the temperature rise caused by the positional deviation of the concentrated sunlight Ls. It is possible to manufacture the solar cell 10 with improved heat resistance, reliability, and weather resistance at low cost with high productivity.

<Embodiment 3>
Based on FIG. 5, the concentrating solar power generation unit according to the present embodiment will be described. The concentrating solar power generation unit according to the present embodiment is configured by arranging a plurality of concentrating solar power generation modules 40m including the solar cell 10 described in the first embodiment. The code at 1 is applied as it is.

  FIG. 5 is a perspective view schematically showing a configuration of a concentrating solar power generation unit according to Embodiment 3 of the present invention.

  The concentrating solar power generation unit 40 according to the present embodiment includes a long frame 44 and a plurality of solar cell modules 40 m arranged along the long frame 44. Note that the concentrating solar power generation module 40m can be configured in an independent manner by being arranged in a separate frame different from the long frame 44.

  Therefore, it is possible to secure a light guide path (columnar optical member 70) having high positional accuracy and stability and to obtain a light condensing characteristic capable of condensing sunlight Ls in a wide wavelength region including a wavelength in a short wavelength region with high accuracy. Therefore, heat resistance and reliability have been improved by improving the light collection efficiency and heat dissipation, improving the power generation efficiency and power generation by reducing the power generation efficiency and preventing the temperature rise caused by the misalignment of the concentrated sunlight Ls Thus, it is possible to obtain a concentrating solar power generation unit 40 with high weather resistance.

  The concentrating solar power generation module 40m includes, for example, a concentrating lens 42 of about 30 cm square, and the concentrating solar power generation unit 40 includes, for example, 5 × 1 (five) concentrating solar power generation modules 40m. It is possible to make it the structure provided with. At this time, the concentrating solar power generation unit 40 constitutes a light receiving surface of about 30 cm × 150 cm, for example.

  Further, the concentrating solar power generation module 40m is connected in series or in parallel with an appropriate number in order to generate necessary power. In the present embodiment, for example, seven concentrating solar power generation units 40 are juxtaposed to form a concentrating solar power generation system (concentrating solar power generation device).

  A concentrating solar power generation system (concentrating solar power generation device) configured by a plurality of concentrating solar power generation units 40 is supported by a support column 81 and is horizontally moved by a tracking mechanism unit (not shown). The condensing lens 42 (incident surface), which is automatically driven in the direction of tracking the sun by the rotation Roth and the rotation Rotv in the vertical direction, is disposed on the surface of the concentrating solar power generation module 40m with respect to the sunlight Lsv. The configuration is oriented in the vertical direction.

  Therefore, the concentrating solar power generation unit 40 according to the present embodiment can be applied to a concentrating solar power generation system having a high concentration magnification. That is, the concentrating solar power generation module 40m according to the present invention can constitute a highly efficient and inexpensive tracking concentrating solar power generation system with good reliability and weather resistance.

  Further, even when a tracking failure due to a tracking error or the like occurs, the solar cell 10 is not likely to be burned, and a highly reliable tracking and concentrating solar power generation system can be obtained.

  The tracking mechanism (tracking drive system) includes an azimuth axis for directing the condenser lens 42 (incident surface) toward the azimuth of the sun and an inclination axis for tilting the condenser lens 42 (incident surface) at the altitude of the sun. Therefore, it is possible to track the sun with high accuracy.

  As a power system of the tracking drive system, a motor and a speed reducer are used to rotate a gear at a predetermined rotational speed to drive in a predetermined direction, and a hydraulic pump and a hydraulic cylinder are used to adjust the cylinder to a predetermined length. There is a method of driving in a predetermined direction, and either method may be used.

  The solar trajectory is calculated in advance by a clock mounted inside the tracking drive system that controls the operation of the tracking drive system, and the concentrating solar power generation module 40m (concentrating solar power generation unit 40) is oriented in the direction of the sun. Are known as solar tracking methods, such as a method for controlling the sun to be directed, and a method for monitoring and controlling the sun direction as needed by attaching a solar sensor such as a photodiode to the tracking drive system. good.

  As described above, the concentrating solar power generation unit 40 according to the present embodiment includes a plurality of solar cell modules 40 m arranged along the long frame 44. By providing the solar cell module 40m with improved condensing characteristics and heat dissipation, there is provided a concentrating solar power generation unit 40 with improved heat generation efficiency and power generation and improved heat resistance, reliability, and weather resistance.

  In other words, a light condensing characteristic capable of concentrating sunlight Ls with high accuracy in a wide wavelength region by securing a light guide having high positional accuracy and stability can be obtained. A concentrating solar power generation unit 40 with high heat resistance, reliability, and weather resistance, which is improved in power generation efficiency and power generation by preventing reduction in power generation efficiency and temperature rise caused by misalignment of the illuminated sunlight Ls; It becomes possible to do.

  In addition, according to the concentrating solar power generation unit 40 according to the present invention, since the long frame 44 and the plurality of solar cell modules 40m arranged along the long frame 44 are provided, a high position is provided. A condensing characteristic capable of concentrating sunlight Ls with high accuracy in a wide wavelength region by securing a light guide having accuracy and stability is obtained, improving condensing characteristics and heat dissipation, and concentrating sunlight Ls. It is possible to improve the power generation efficiency and power generation by reducing the power generation efficiency and the temperature rise caused by the displacement of the position, thereby improving the heat resistance, reliability, and weather resistance.

It is sectional drawing which shows the solar cell and concentrating solar power generation module which concern on Embodiment 1 of this invention. FIG. 2 is an enlarged plan view showing a state in which the solar cell shown in FIG. 1 is enlarged from the condenser lens side. It is an expanded sectional view which shows the cross section in the arrow YY direction of FIG. It is process drawing explaining the solar cell manufacturing method which concerns on Embodiment 2 of this invention, and shows the state which mounted the solar cell element in the receiver board | substrate with the cross section in the arrow XX direction of FIG. It is process drawing explaining the solar cell manufacturing method which concerns on Embodiment 2 of this invention, and shows the state which mounted the optical holding | maintenance part in the receiver board | substrate with the cross section in the arrow XX direction of FIG. It is process drawing explaining the solar cell manufacturing method which concerns on Embodiment 2 of this invention, and shows the state which inject | poured sealing resin into the space which an optical holding part comprises between a receiver board | substrate with arrow X- of FIG. Shown in cross section in X direction. It is process drawing explaining the solar cell manufacturing method which concerns on Embodiment 2 of this invention, and shows the state which mounted the columnar optical member in the optical holding part in the cross section in the arrow XX direction of FIG. It is a perspective view which shows roughly the structure of the concentrating photovoltaic power generation unit which concerns on Embodiment 3 of this invention. It is sectional drawing which shows the structure of the concentrating photovoltaic power generation module applied to the conventional tracking concentrating photovoltaic power generation apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Solar cell 11 Solar cell element 20 Receiver board | substrate 21 Adhesion part 40 Concentration type photovoltaic power generation unit 40m Concentration type photovoltaic power generation module 42 Condensing lens 44 Long frame 70 Columnar optical member (light guide path)
70c Axial corner portion 70f Incident surface 70r Irradiation surface 70s Optical path inclined surface 72 Optical holding portion 72g Notch portion 72h Fin 72w Holding wall (holding inclined surface)
73 Resin sealing portion 73r Sealing resin Af Condensing region Hh, Hp Height Lax Optical axis Ls, Lsa, Lsb, Lss Sunlight Roth Horizontal rotation Rotv Vertical rotation Tr, Ts Thickness Wb Center of gravity position

Claims (8)

A solar cell comprising a solar cell element that photoelectrically converts sunlight condensed by a condenser lens, a receiver substrate on which the solar cell element is placed, and a resin sealing portion that resin-seals the solar cell element Because
A columnar optical member constituting a light guide for guiding the condensed sunlight to the solar cell element;
A solar cell comprising: a holding wall that holds the columnar optical member; and an optical holding portion that covers the resin sealing portion and is placed on the receiver substrate. The solar cell according to claim 1,
The columnar optical member has an optical path inclined surface for collecting sunlight on the solar cell element, and the holding wall is a holding inclined surface aligned with the optical path inclined surface. The solar cell according to claim 1 or 2, wherein
The solar cell according to claim 1, wherein the optical holding unit is in contact with a metal base base of the receiver substrate. A solar cell according to any one of claims 1 to 3,
The optical holding unit includes comb-shaped fins on an outer peripheral side surface. It is a solar cell as described in any one of Claim 1 thru | or 4, Comprising:
The columnar optical member is a quadrangular column, and the optical holding unit includes a groove-shaped notch that surrounds an axial corner of the square column. A solar cell according to any one of claims 1 to 5,
The said resin sealing part is made thinner than the surrounding area between the said columnar optical member and the said solar cell element. The solar cell characterized by the above-mentioned. A concentrating solar power generation module comprising a condensing lens that condenses sunlight and a solar cell that photoelectrically converts sunlight collected by the condensing lens,
The said solar cell is a solar cell as described in any one of Claim 1 thru | or 6, The concentrating solar power generation module characterized by the above-mentioned. A solar cell element that photoelectrically converts sunlight collected by the condenser lens, a receiver substrate on which the solar cell element is placed, a resin sealing portion that resin-seals the solar cell element, and is condensed A columnar optical member that constitutes a light guide for guiding sunlight to the solar cell element, and a holding wall that holds the columnar optical member, and is placed on the receiver substrate so as to cover the resin sealing portion A solar cell manufacturing method for manufacturing a solar cell comprising an optical holding unit,
An optical holding part preparing step of forming a metal and preparing the optical holding part;
An optical holder placement step of placing the optical holder in contact with the receiver substrate on the outer periphery of the solar cell element; and
A resin injection step of injecting a sealing resin for forming the resin sealing portion into the space formed by the optical holding portion and the receiver substrate;
An optical member placing step of placing the columnar optical member on the holding wall.

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