EP2936566A1 - Cellule photovoltaïque tolérant l'ajustement - Google Patents

Cellule photovoltaïque tolérant l'ajustement

Info

Publication number
EP2936566A1
EP2936566A1 EP13811523.3A EP13811523A EP2936566A1 EP 2936566 A1 EP2936566 A1 EP 2936566A1 EP 13811523 A EP13811523 A EP 13811523A EP 2936566 A1 EP2936566 A1 EP 2936566A1
Authority
EP
European Patent Office
Prior art keywords
segment
sub
photovoltaic cell
subcell
cells
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP13811523.3A
Other languages
German (de)
English (en)
Inventor
Andreas Bett
Simon PHILIPPS
Kasimir REICHMUTH
Henning HELMERS
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Original Assignee
Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV filed Critical Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Publication of EP2936566A1 publication Critical patent/EP2936566A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
    • H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by potential barriers
    • H01L31/068—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by potential barriers the potential barriers being only of the PN homojunction type, e.g. bulk silicon PN homojunction solar cells or thin film polycrystalline silicon PN homojunction solar cells
    • H01L31/0687—Multiple junction or tandem solar cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
    • H01L31/054—Optical elements directly associated or integrated with the PV cell, e.g. light-reflecting means or light-concentrating means
    • H01L31/0543—Optical elements directly associated or integrated with the PV cell, e.g. light-reflecting means or light-concentrating means comprising light concentrating means of the refractive type, e.g. lenses
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/52—PV systems with concentrators
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/544—Solar cells from Group III-V materials

Definitions

  • the invention relates to a photovoltaic cell with at least four segment regions, which can be exposed to electromagnetic radiation directly, and at least three sub-segments, to which these segment regions are distributed.
  • the arrangement can be chosen so that the segment areas are arranged only laterally side by side; but it can also be a photovoltaic
  • Multiple cell can be selected, in which the different segment areas in the at least two superimposed sub-cells of the multiple cell are present.
  • the upper part cell has a kind of "recesses", so that the direct exposure to electromagnetic radiation for two separate
  • Sunlight into electrical energy is not only limited to sunlight, but can also be used to convert light or general electromagnetic radiation - from other sources.
  • optical power transmission also known as "power-over-fiber”
  • photovoltaic cells with artificial light or more generally: artificially generated electromagnetic radiation
  • irradiated which is generated for example by means of lasers, LEDs or halogen lamps, for example, to provide small consumers with energy. It can therefore be an energy transfer (more precisely: power transmission) without metal cable and hereby shorts, damage due to overvoltages and the like, can be avoided.
  • the transfer of artificial Electromagnetic radiation to the photovoltaic cell takes place either via the air or by means of dense media such as fiber optic cables.
  • the voltage and the conversion efficiency of solar cells can be increased, as is known, with monolithic multiple solar cells.
  • H several solar sub-cells are stacked on top of each other.
  • the currently best solar cells consist of three pn junctions in different semiconductor materials, which are internally connected in series via tunnel diodes.
  • the next generation of multiple solar cells will contain four or more pn junctions to further increase efficiency.
  • stacks of two sub-cells i.e., tandem cells
  • two pn junctions consisting of a semiconductor material - with a tunnel diode - connected in series. Based on the semiconductor material GaAs, open terminal voltages of 2.4 V were achieved.
  • the interconnection of series-connected pn junctions in multiple cells with stacked sub-cells can be monolithic or mechanical.
  • the pn junctions consist of semiconductor materials with different bandgap, mostly of germanium and / or so-called III-V compound semiconductors, which are material compositions of the elements of III. and V. main group, for example gallium arsenide, gallium indium arsenide or gallium indium phosphide, or other semiconductors, such as Il-VI compound semiconductors.
  • III-V compound semiconductors which are material compositions of the elements of III. and V. main group, for example gallium arsenide, gallium indium arsenide or gallium indium phosphide, or other semiconductors, such as Il-VI compound semiconductors.
  • the bandgap energy of the pn junctions increases from the lowest to the uppermost cell.
  • Multiple solar cells are often realized as monolithic stacks.
  • the different semiconductor layers are thus grown or stacked directly on top of each other.
  • MOVPE metalorganic vapor phase epitaxy
  • LPE Liquid Phase Epitaxy
  • MBE Molecular Beam Epitaxy
  • the back is usually metallized over the entire surface. These metallizations serve as front and
  • metal connectors such as wire bonds or metal bands used.
  • bypass diode is a diode that is connected anti-parallel to the solar cell and opens a further current path next to the solar cell.
  • the relevant solar cell is not loaded (which could destroy it), but the current flows through the bypass diode.
  • the bypass diode will turn off to avoid losses.
  • concentrator modules with high current densities, but also generally in series connection each individual separate solar cell is ideally protected with a bypass diode.
  • Tunnel diodes are highly doped diodes, which are inversely connected to the solar cells. This means that the n-doped layer of the solar cell is followed by the highly doped n-layer (usually written: n ++ ) of the tunnel diode. After the highly doped p-layer (p ++ ) of the tunnel diode, the p-doped layer follows the next solar cell.
  • Typical dopants of the tunnel diodes are in the range of 1 * 10 19 to over 1 * 10 20 1 / cm 3 .
  • the dopings of the solar cells are in the range of 1 * 1 0 15 and 8 * 1 0 18 1 / cm 3 .
  • To the layers of the solar cells and tunnel diodes come additional layers such as
  • WO 1 980US00945 already describes monolithically integrated series-connected photovoltaic cells in which a plurality of photovoltaic single cells or
  • the concentration of light is realized by reflective or refractive optics, such as mirrors or lenses.
  • the light is focused on the solar cell.
  • the concentration factor of light is up to 50-fold in low-concentration systems, 50 to 200-fold in medium concentrations and 1 00 to more than 1 500 times in high-concentration systems. Due to the concentration of light, the solar cell area can be reduced by about the concentration factor. Through the use of cost-effective optics costs can be minimized. At tightly packed
  • Concentrator modules the irradiation is typically approximately homogeneous, ie all sub-cells are then the same size to achieve a current adjustment.
  • photovoltaic cells can - as already mentioned - be used in the optical power transmission.
  • concentrator optics may be inaccurately positioned to the solar cell, shape errors or microstructural defects of the optics may be present, variations due to
  • Power transmission is particularly problematic inaccurate adjustment of the radiation source and / or a radiation transmission medium (for example the use of lasers as a radiation source and glass fibers as a light guide).
  • problems may arise due to the use of secondary optics or obliquely incident light on the photovoltaic cell.
  • the present application is therefore based on the object to overcome the disadvantages of the prior art and to specify a adjustment-tolerant photovoltaic cell with multiple sub-segments.
  • the photovoltaic cell should be current adapted and generate a high voltage.
  • Another object is to provide a photovoltaic cell having a plurality of sub-cells that is tolerant to deviations from the ideal power distribution of the incident light.
  • Another object is to provide a photovoltaic cell with several sub-cells, which is tolerant of temperature fluctuations. At least one of these tasks is governed by the subject matter of the independent
  • Such a photovoltaic cell can be used both for the optical power transmission in the field of power over fiber applications and for applications in which not a laser is used as a radiation source, but any other light source or radiation source, as well as for
  • Concentrator systems are used. The concept can realize its great advantages, in particular, if the photovoltaic cell is manufactured by means of a technology which allows a sequential layer deposition (for example MOVPE, MBE or vapor deposition).
  • a sequential layer deposition for example MOVPE, MBE or vapor deposition.
  • An alignment tolerant photovoltaic cell has a front side, which (in operation) faces the irradiated electromagnetic radiation and a rear side, which faces away from this radiation.
  • the front side further comprises at least three sub-segments, on which the electromagnetic radiation can impinge directly. It goes without saying that the subsegments are each formed of a semiconductor material and (exactly) allow a pn junction.
  • Part segment is arranged more, by which an absorption of the incident electromagnetic radiation could take place.
  • Partial segment or front side which is directly incident or impinged by electromagnetic radiation, that it is the sub-segment, the z. B. in one
  • monolithic arrangement has the spatially furthest above (based on the radiated electromagnetic radiation) arranged pn junction.
  • the front of the photovoltaic cell need not be a flat surface; rather, a stepped arrangement may be present with the front of the photovoltaic cell passing through the front of each element of the steps is formed, so each sub-segment or each as defined below
  • the front side has at least three subsegments; these three subsegments are again in the form of at least four separate ones
  • a sub-segment may be identical to a segment region, because the sub-segment is designed such that full-surface electromagnetic radiation can impinge directly on the front side;
  • the sub-segment can also have two segment regions, which can impinge directly on electromagnetic radiation, between which there is an area of the sub-segment, on which no electromagnetic radiation can impinge directly, for example, because over this area, a further semiconductor layer, the electromagnetic radiation at least partially absorbed , is arranged, for example in the form of an overlying sub-segment.
  • the photovoltaic cell according to the invention is arranged in the form of a first segment type and at least one sub-segment in the form of a second segment type arranged such that at least two separate segment regions are formed for the first and the second segment type, to which electromagnetic radiation can impinge directly.
  • first segment type and at least one sub-segment in the form of a second segment type arranged such that at least two separate segment regions are formed for the first and the second segment type, to which electromagnetic radiation can impinge directly.
  • Embodiments are possible in which the two separate segment areas are not interrupted by an area to which electromagnetic radiation can not impinge directly.
  • the incident electromagnetic radiation has such a low radiation intensity in the "separating region” that it comes close to or substantially equal to an interruption of the segment regions and thus of separate ones
  • Segment areas can be spoken. Such an embodiment is, for example, when - as is usually the case - the maximum intensity of the incident electromagnetic radiation in the region of the geometric center of gravity of the front is irradiated. Due to the frequently existing Gaussian distribution of the radiation intensity, the radiation intensity then decreases sharply starting from the geometric center of gravity, so that only a relatively low radiation intensity is present in the outer regions of the photovoltaic cell, which is for example at most 10% of the maximum intensity.
  • the area which is formed by a concentric circle around the geometric center of gravity, the area of which is 50% of the front side (can directly hit the electromagnetic radiation).
  • the above definition "at least in the area of the geometrical center of gravity of the front two separate segment areas” therefore means that at least in a concentric circle around the geometric center of gravity whose area is 50% of the front, the definition of each other completely separate
  • Segment areas is valid. As mentioned above, the term subsegments links to the electronic
  • At least two sub-segments of the first segment type are connected in parallel to one another and / or two sub-segments are connected to one another via a transition region, via which a lateral current flow
  • a lateral region guaranteeing the lateral current flow is understood to mean that not only a lateral current flow ensuring connection can take place between two segment regions by means of a busbar or the like, but also (for example for process economic reasons due to an etching process) a web of semiconductor material remains between two segment areas, which is formed of the same material as these two segment areas, but in the result electronically fulfills the same or a similar function as a bus-bar.
  • the diameter of this transition region is small compared to the maximum dimensions of the sub-segments.
  • Maximum expansion is the longest distance that can be formed between any two points on the edges of the subsegment (in the case of a circular sector, either the radius or the chord of the circle in the case of a square)
  • the diameter of the transition region is in particular at most 20%, usually at most 10%, for example at most 5% of the maximum extent of one of the two sub-segments connected to the transition region.
  • the photovoltaic cell according to the invention can be present either in a stepped arrangement with sub-segments of the front side (hereinafter often referred to as “stepped embodiment”) in different sub-cells or in an arrangement with laterally juxtaposed sub-segments of the front side (hereinafter often referred to as "lateral embodiment”) ,
  • stepped embodiment sub-segments of the front side
  • lateral embodiment laterally juxtaposed sub-segments of the front side
  • the photovoltaic cell comprises at least a first subcell and a second subcell disposed below the first subcell.
  • the first segment type is then present at least in the first subcell and the second segment type at least in the second subcell.
  • the front side surface of the first subcell is then smaller than the front side surface of the underlying second subcell, thereby forming the stepped arrangement.
  • at least one first subcell is formed, which is formed by the first segment type, under which the second subcell is arranged so that two separate at least in the region of the geometric center of gravity of the front side on the second subcell Segment regions are formed and in which the first subcell interconnected by two parallel and / or a lateral current flow
  • lateral embodiment (with laterally arranged sub-segments) are at least four sub-segments, of which two sub-segments together form the second segment type and are therefore interconnected in parallel and / or interconnected by a lateral current flow ensuring transition area and two other sub-segments form first segment type, which also connected in parallel and / or via a lateral current flow
  • transition region are interconnected.
  • laterally juxtaposed segment regions are present.
  • Segment area groups are interconnected serially). If, for example, a circular photovoltaic cell is used, in which the at least four segment regions are present, a partial shading of subsegments and / or segment regions of the first segment type and subsegments and / or segment segments and / or segment regions of the first segment type and / or segment segments and / or segment segments is always always simultaneously effected during pivoting of a circular light spot arranged congruently over the circular photovoltaic cell. or segment areas of the second segment type. After the segment areas and / or sub-segments of a segment type are always connected in parallel or connected to each other, but then a shaded segment area is always with a not shaded
  • the stepped embodiment brings with it a further advantage: As already explained at the beginning, the current adaptation of the subcells contributes
  • photovoltaic multiple cells in certain irradiations is a major technical challenge.
  • the decisive factor here is first the selection of the semiconductor material used.
  • other material properties, the charge carrier mobility and the lifetime of the semiconductor material are first the selection of the semiconductor material used.
  • nitride-containing layers such as GalnNAs
  • the lower part cell must contain comparatively thick absorber layers in order to be sufficient To produce electricity.
  • the material quality and thus the diffusion length of the charge carriers is low, only charge carriers from a small part of the absorber layers can contribute to the current, so that the lower part cell does not produce enough current.
  • the current adjustment of multiple cells in the prior art must also be designed for a particular operating temperature. Since temperature affects critical material parameters (such as band gap, conductivity, and mobilities), deviating temperatures are not ideal
  • Embodiments of the preceding paragraph thus represent a separate inventive aspect, also independent of the specific embodiment with two separate segment areas in the second subcell and the presence of two sub-segments in the first subcell, in particular what optical applications
  • both in the lateral embodiment and in the stepped embodiment more than one or two sub-cells can be present.
  • two or more (serially interconnected) sub-cells can be arranged one above the other.
  • Embodiment may also be three or more (serially interconnected) sub-cells
  • sub-cell groups for example, the two uppermost sub-cells may have a different surface, which is directly exposed to electromagnetic radiation;
  • at least three sub-cells or sub-cell groups may be formed so that they each occupy a larger area than the overlying sub-cell or sub-cell group and therefore each have segment areas that are directly exposed to electromagnetic radiation.
  • a third subcell is present in a stepped embodiment, then, as is necessary from the electronic definitions, a third segment type is of course also present.
  • first sub-layer or a first sub-segment "on" a second sub-layer is arranged when the first sub-layer or the first sub-segment directly in direct mechanical and / or electrical contact is applied to the second sub-layer or that only an indirect contact is designated, in which further layers and the like between the first sub-layer or the first sub-segment and the second sub-layer are arranged.
  • further layers are, for example, the tunnel diodes described at the beginning or others usually in solar cells and
  • Photovoltaic cells present layers.
  • the photovoltaic cell is a multiple cell (ie a photovoltaic cell with a lateral embodiment, which has at least two subcells or a photovoltaic cell with a stepped embodiment), in which at least two of the (at least two) sub-cells arranged one above the other are made
  • Room temperature (25 ° C) is a maximum of 0.1 eV.
  • the band gap is determined by evaluating the spectral sensitivity of the finished component.
  • This embodiment is particularly useful when monochromatic light of a certain wavelength is to be converted. This can be especially true
  • the band gap of the sub-cells need only be aligned to exactly one wavelength and therefore such an embodiment is advantageous.
  • there are at least two sub-cells of different materials that is, there is at least one subcell formed of a semiconductor material that differs from the material of at least one further subcell such that not more can be said of materials having substantially the same bandgap.
  • a photovoltaic cell according to this embodiment can also be designed such that the energy band gap of the sub-cells decreases from the uppermost completely electromagnetic radiation-exposed subcell to the sub-cells below.
  • Embodiment be realized.
  • an antireflection coating is applied in the stepped arrangement after structuring the steps. If the stack comprises sub-cells of the same materials, the antireflection coating can be optimized according to known methods, simultaneously for all these sub-cells (since the optimization is carried out for a specific semiconductor structure).
  • subcells made of materials of poor material quality are chosen to be wider so that they generate the same currents as subcells of good materials in the stack.
  • partial cell sequences may be present within a photovoltaic cell with a stepped embodiment in which each subcell occupies the same area within a subcell sequence, but in the case of two successive subcell sequences the subcell sequence lying below occupies a larger area than the subcell sequence lying above it.
  • a subcell sequence which in the prior art is usually referred to as a "multiple cell" in its own right
  • the photovoltaic cell is a multiple cell, which is monolithic.
  • Such a photovoltaic cell can be produced by means of the epitaxy method described above.
  • the photovoltaic cell is a multiple cell, in which the sub-cells are connected by means of tunnel diodes.
  • the tunnel diodes are used to change the polarity and conduct the current in both directions with a small voltage drop.
  • the photovoltaic cell or the sub-cells contained therein may be circular, square, rectangular or elliptical or substantially have such a geometry; these embodiments are likely to prove particularly suitable for manufacturing and economic reasons particularly suitable.
  • other geometries such as triangular or polygonal, may also be formed next to it.
  • a homogeneous power distribution of the incident light can be assumed as a first approximation (even if, in reality, the above deviations from the ideal power distribution exist - but these deviations are not or poorly predictable).
  • the irradiation of the photovoltaic cell and thus of the sub-segments At least in applications in the area of concentrator modules, the irradiation of the photovoltaic cell and thus of the sub-segments
  • secondary optics also be approximately homogeneous. From this it follows that the area of the groups of sub-segments of the same segment type which are directly susceptible to electromagnetic radiation should, to a first approximation, be substantially equal.
  • Concentrator modules will be more likely to have point-symmetric radiation, in which the incident radiation often has a power distribution that is in the
  • Segment types that are directly exposed to electromagnetic radiation, in a first approximation, have a substantially equal with radiation directly acted upon surface.
  • the segment regions of the first segment type have an area that is substantially the same size as that of the segment regions of the second segment type (and each further segment type), at least in the area of the geometric center of gravity of the front side.
  • substantially equal here and in the following means that the accumulated area (which can be directly exposed to electromagnetic radiation) of the segment type with the smallest surface area amounts to at least 80% of the cumulative area of the area
  • Segment type with the largest surface area As a rule, the proportion will even be at least 90% and often even at least 95%. If there are only two types of segments, then the accumulated area of the first segment type is between 80 and 125%, usually between 90 and 1 1 1% and often between 95 and 105% of the accumulated area of the segment segments of the second segment type. Especially for power applications, these embodiments do not apply "only" to the entire area of the photovoltaic cell's segment areas, but in particular to the areas lying in the area of the geometric center of gravity of the front side (which is defined above). It goes without saying, however, that the embodiment of the preceding paragraph refers to an irradiation that impinges homogeneously on the photovoltaic cell. In the case of inhomogeneous irradiation, the area must still be weighted with the radiation intensity incident on this area.
  • segment regions of the first segment type and the segment regions of the second segment type alternate at least in the region of the geometric center of gravity of the front side. The same applies if more than two types of segments exist; here too, according to this
  • Embodiment be selected an alternate arrangement, taking particular account of the fact that two segments of a segment type not or only in very small "touch areas" come to lie next to each other.
  • the geometric arrangement has to be made, is known in the art and results, moreover, also for geometric considerations without much action.
  • the alternating arrangement is not necessarily a given geometric structure; in more exotic geometric arrangements of segment areas and sub-segments embodiments are certainly conceivable in which an alternating structure is not unambiguously indicated for these geometric shapes.
  • a light beam with homogeneous light distribution radiates onto the front side of the photovoltaic cell, which forms a circle on the front side with a circular area which is exactly 80% of the total area of the front side is. This is - as always under this application, when it comes to
  • Area ratio of segment areas of the first segment type and the second segment type between 0.95 and 1, 05, in particular between 0.98 and 1, 02 is located.
  • Segment areas selected so that they belong to different segment types.
  • Segment areas belong to the same segment types and in the case of a number of segment areas that can be divided by the number of segment types but not additionally by 2
  • geometric center of gravity of the front is drawn a variety of straight lines. In at least one of these lines, often more of these lines and often also In each of these straight lines, it is the case that the mutually mirror-symmetrical straight sections (the axis of symmetry being the geometric center of gravity) extend through segment areas which, as defined above, belong to different or identical segment types. As with the above embodiments, these geometric conditions apply at least in the area of the geometric
  • Segment segment groups or segment types are at least in the region of the geometric center of gravity of the front side.
  • the segment regions essentially form the shape of a circular sector, a trapezoid, a triangle, a rectangle or a square.
  • “Substantially” means that deviations from the ideal geometry are possible to a certain extent; It goes without saying that the ideal production geometry can never be realized by the chosen production processes and, in addition, deviations from the ideal geometry must be made anyway in the case of transition regions which are intended to ensure a lateral power supply.
  • the photovoltaic cell according to the invention has at least six, in particular at least eight, for example at least twelve separate segment regions.
  • the number of segment areas is also dependent on whether there is a stepped arrangement or a lateral arrangement of the segment areas.
  • the formation of the "stage" is realized, in particular, by etching methods and the like, in which there need be no insulating sections between the areas. For possible etch processes, see the dry etch and wet etch processes as described in H. Helmers et al. in IEEE Transactions on Electron Devices Vol. 57, page 3355 ff (201 0), the relevant disclosure of which is hereby fully incorporated by reference.
  • the selected upper limit is essentially the
  • the photovoltaic cell is a multiple cell with three to six stacked sub-cells. This applies to both the stepped embodiment and the lateral embodiment.
  • the photovoltaic cell is a solar cell, in particular a solar cell, which is preceded by a concentrator optics.
  • the photovoltaic cell is a cell applications for optical power transmission, for example, generated by means of a laser electromagnetic radiation.
  • At least one of the objects according to the invention is also achieved by a power generation arrangement comprising a photovoltaic cell according to at least one of the embodiments described above, wherein besides the
  • Such a means for exposure to radiation may in particular a
  • Light source or general radiation source such as a laser light source to be.
  • the light source can generate monochromatic radiation, in particular
  • Infrared radiation visible light or UV radiation; but it can also contain radiation of larger wavelength ranges or be a radiation approximated to sunlight.
  • the means for applying may comprise a concentrator optics for focusing electromagnetic radiation.
  • This concentrator optics can be particularly useful if the arrangement includes one or more solar cells and sunlight by means of a concentrator on the Solar cell to be focused.
  • the arrangement for generating electricity as a means for applying a light guide which is arranged between the light source and the photovoltaic cell, that a uniform loading of the segmental regions of the photovoltaic cell is possible with light. It goes without saying that the geometric center of gravity of the exit surface of the light guide should come to rest as possible above the geometric center of gravity of the front of the solar cell. According to a further embodiment, in addition to the light guide still another
  • Secondary optics which can serve as a "homogenizer”. This can be for example a microlens array.
  • means are provided in addition to the photovoltaic cell, with which causes the highest radiation intensity, which is generated by the light source or by the concentrator optics on the
  • Front of the photovoltaic cell is applied, approximately incident in the geometric center of gravity of the front.
  • Approximately in the geometric center of gravity here means that the intensity maximum on a straight line between the
  • the invention has the advantage that by segmenting the cell and / or structuring the cell by steps, a tolerance to a misalignment of the photovoltaic Cell and irradiated thereon light can be increased. On the one hand, this can be achieved by designing the surface of the semiconductor regions in a stepped manner, on the other hand by segmenting the cell with sub-segments connected in series, whereby the tolerance to inhomogeneous illumination or misalignment is achieved here by parallel connection of different segment groups.
  • the stepped multiple cell additionally generates the advantage that a very high voltage is achieved. It is crucial that the stepped structure allows a current adjustment even if an adjustment by the partial cell thickness is not possible. In this way, in particular more sub-cells can be stacked and it can be used materials in which an increase in the current by adjusting the thickness is no longer possible (too small diffusion length of the charge carriers).
  • the stepped multiple cell described has the potential to become the standard in power-over-fiber applications.
  • the field of concentrating photovoltaics the
  • Figure 1 shows an embodiment in which sub-segments are arranged laterally to each other, and provides a serial connection of the sub-segments according to the prior art.
  • H here, four square sub-segments 1 of the photovoltaic cell are again arranged in a square.
  • the subsegments are electrical
  • Contact surfaces 3, 3a and 3b are electrically connected via, for example, wire bonds or conductor strips 9. 3a and 3b are electrically isolated from each other.
  • This embodiment also shows a bypass diode 5 with two bypass diode carriers 4 and 6 associated with the two electrical contacts.
  • the photovoltaic cell is here arranged on a substrate 7 and separated from it by an electrical insulation 8.
  • Figure 2 shows a photovoltaic multiple cell according to the prior art. In this case, a plurality of III-V semiconductor layers are provided. There are three sub-cells 1 1, 12, 1 3 on p-doped substrate. Between the sub-cells 1 1, 1 2, 13 tunnel diodes 20 are arranged. The sub-cells 1 1, 1 2, 13 are connected in series with each other by the tunnel diodes 20.
  • a metallization 21 On the front of the cell there is a metallization 21 and an indicated bond wire 22. Between or on the arranged for example in the form of bus bars or over the entire surface on the front metallization may also be formed a dielectric antireflection layer. Finally, a rear-side contact 23 is arranged on the rear side of the solar cell.
  • FIG. 3 shows the simplest arrangement of the photovoltaic cell according to the invention in the case of a circular geometry of the photovoltaic cell.
  • the Sub-segments 1 A, 1 B, 1 C and 1 D each formed as a quarter circle.
  • the geometric center of gravity of the surface here is a punctiform, the lateral current flow between the "parallel" sub-segments 1 A and 1 C guaranteed
  • Transition region 31 is provided, which is located in the geometric center of gravity 50. Alternatively, however, a parallel connection of the subsegments 1 A and 1 C by means of a conductor path arranged outside the cell could also take place here. Between the sub-segments 1 A and 1 B, 1 B and 1 C and 1 C and 1 D are along the lines 32 in the case of the stepped embodiment, the lateral edges of the top part cell 1 1 and in the case of the lateral embodiment, an isolation trench.
  • FIG. 3a shows a sectional view of the photovoltaic cell along the dashed line S for the lateral embodiment. It can be seen that the sub-segment 1 A is separated from the sub-segment 1 B via an isolation trench 32.
  • Figure 3b shows a sectional view of the stepped embodiment of the photovoltaic cell.
  • the sub-segment 1 A is a part of the sub-cell 1 1 and the sub-segments 1 B and 1 D is a part of the sub-cell 1 2. Only a portion of the sub-segment 1 B / 1 D is directly exposed to electromagnetic radiation 100 from a radiation source. Accordingly, the result
  • Segment areas 2A and 2 B which can be directly exposed to electromagnetic radiation.
  • the stepped arrangement therefore, only one partial segment 1 B / 1 D is present in the region of the partial cell 12, in which two segment regions 2 B and 2 D are present (not shown here).
  • FIGS. 3c and 3d show the result of a slight light
  • segment areas are increased. This is shown in FIG. 4 with six segment regions 2 A, 2 B, 2 C, 2 D, 2 E, 2 F, which can be present both in the stepped and in the lateral embodiment.
  • segment areas 2A, 2C and 2E on the one hand and 2 B, 2D and 2 F on the other hand are connected either in parallel with one another or together form part of the same subcell.
  • FIG. 5 shows an ideal case with regard to shading during displacement of the
  • the photovoltaic cell here has a large number (namely 48)
  • Very small structures can be realized here by RIE etching with vertical edges, for example, without generating additional area losses through the etching edges. If the structures are small enough, the transverse conduction in the emitter or transverse conduction layer of the cells will have low loss and it will be possible to dispense with front-side metallization, in particular in the lower cell, in a stepped arrangement; this simplifies the
  • the area of the sub-segments of the same segment type is the same size if homogeneous illumination is present.
  • the embodiment according to FIG. 5 is less suitable for the lateral arrangement, since here the area occupied by the isolation trenches has a negative effect on the conversion efficiency.
  • FIG. 6 shows the continuation of FIG. 5 in the case of a stepped arrangement with three partial cells.
  • FIG. 6a shows the sectional view with the three sub-cells 11, 12 and 13 and the four exemplary segment areas 2A, 2B, 2C and 2D.
  • Segment region 2A corresponds here to subsegment 1 A, segment region 2 B to subsegment 1 B, segment region 2 C to subsegment 1 C, which extends over the entire circular area, and segment region 2 D to subsegment 1 D, whereby the subcell 1 located under subsegment 1 D 1 also to the left continues (not shown) and here again forms a directly acted upon by electromagnetic radiation segment region 2 E.
  • the individual sub-cells 1 1, 12 and 1 3 can here by independent
  • Multiple cells may be formed, for example GaAs tandem cells. In this way, cells with about 6 V can be realized with three stacked and stepped double cells.
  • FIG. 7 a shows the region of FIG. 7 bordered by the dashed line.
  • Segment areas are because they are present in the upper part cell 1 1.
  • transparent transverse conductive layers can be used. If the structures are small enough, the transverse conduction in the emitter or cross conduction layer of the cells becomes low-loss and front-side metallization can be dispensed with; This simplifies processing and reduces costs.
  • the transition region 31 is not designed (only) in the region of the geometric center of gravity 50 to ensure a lateral current flow.
  • FIG. 8 and FIG. 8 a correspond to FIGS. 7 and 7 a. It can be seen in FIGS. 8 and 8a that a structured front-side metallization 21 is applied to support the lateral current flow between the structured elements.
  • FIG. 9 and FIG. 9a to a certain extent represent the combination of embodiment 7 with a multiple cell with three sub-cells 11, 12, 13 (as also shown in the transition from FIG. 5 to FIG. 6).
  • FIG. 9a the sectional view for the segment regions 2a, 2b, 2c, 2d is again shown by way of example, and the associated subsegments are shown.
  • FIG. 10 again shows the arrangement with the stepped multiple cell, in which - as stated above - the sub-cells 1 1, 1 2, 13,... Are here with “subcell 1", “subcell 2 ",” subcell 3 to (n-1) ",” subcell n “, where n is the total number of subcells, and may be made of the same or different materials, with tunnel diodes 20 in between are selected so that directly lightable segment areas 2A, the pair 2B / 2C, and the two pairs 2 (n-1) '/ 2 (n-1) * and
  • FIG. 10a shows the same arrangement in which each subcell is again formed by three "subcell cells" of the same area connected via tunnel diodes, so that, to a certain extent, a stack is produced with a number of subcells which is three times as high as the number of stages.
  • the steps may in this case each contain sub-cells, which are formed from the same material and are accordingly suitable for monochromatic light.
  • FIG. 10b shows the same arrangement as FIG. 10a; however, examples of different materials of the sub-cells are explicitly listed here.
  • Figure 10c shows a special case for Figure 10a, again in the sectional view; in this case, the stepped arrangement of two dual cells 1 1 and 1 2 as sub-cells, which are designed for monochromatic light.
  • the individual sub-cells and sub-cells consist of the same materials.
  • the GaAs selected in the figure may also be GalnAs or any other suitable material as described above.
  • the area ratios should be
  • Transverse layers 21 may be a material having a larger bandgap which is transparent to the incident, for example monochromatic, irradiation, and the like
  • Figure 1 1 shows an embodiment, which shows by way of example, as a stepped
  • Arrangement can be selected if there is a non-homogeneous profile of the incident illumination, for example, a Gauss profile.
  • a non-homogeneous profile of the incident illumination for example, a Gauss profile.
  • Segment areas formed areas not equal in size, but adapted to the intensity profile.
  • the upper part cell 1 which - as stated above - also a
  • Multiple cell can be here exposed to a higher intensity than the lower part cell 1 2 and therefore has the smaller surface area than that directly
  • Figures 12a and 12b show an embodiment in which a stepped
  • Figure 12a shows the top view
  • Figure 12b shows a side view. It is about a
  • segmented middle subcell 1 1 and a segmented lower subcell 12.
  • the entire uppermost subcell 1 3 is formed by the sub-segment 1 A, the middle subcell 1 1 completely through the sub-segment 1 B and the lowest sub-cell 1 2 through the sub-segments 1 C, 1 D, 1 E and 1 F, each one
  • the uppermost subcell 13 accordingly has a
  • Segment area 2 B and the sub-cell 12 each have segment areas 2C, 2D, 2 E and 2 F, each occupying the area of a quarter-ring.
  • Such an embodiment is particularly useful for homogeneous irradiation, since it is irrelevant whether there is a segmentation in the region of the geometric center of gravity, but it is only important that with a slight pivoting or adjustment tolerance in the edge region and the corresponding shading can be compensated , It goes without saying that between the sub-cells 1 1 and 12, a layer should be formed, at least in partial areas, which ensures the serial / parallel interconnection of the sub-cells and sub-segments according to the invention.
  • Figure 1 3 shows a corresponding to Figure 1 2 arrangement in plan view.
  • a stepped embodiment is provided in which the segment regions of the upper semiconductor layers are not connected in parallel or form a single segment region but are connected to the other segment regions only in the form of the complete triple cell present in the sub-segment. Due to, for example, a Gaussian distribution of the incident light, the area of the innermost circle is chosen to be significantly smaller than that of the middle circle and thus the area of the annulus between the two middle circle lines is greater than that of the innermost circle;
  • Figure 1 3 shows again the result when pivoting the light spot 1 01, for example due to misalignment. Less illuminated segments generate less power; however, due to the partial parallel connection, the current adaptation of the series connection is obtained as illustrated by the diagram on the right. As already stated above, the tolerance can be increased here by an increased number of segments.
  • Figure 14 shows an embodiment in which the stepped embodiment and lateral embodiment are completely united together.
  • the dashed line defines the isolation trench 32 between the subsegments.
  • the subsegments are each designed as a tandem cell, wherein in each case the upper and the lower subcell of a subsegment are present in the stepped embodiment.
  • Segment areas of the upper sub-cells 2 E, 2 F, 2 G, 2 H are not directly interconnected here; Rather, the sub-segments 1 A and 1 C and 1 B and 1 D are connected in parallel to each other and the sub-segment pairs 1 A / 1 C and 1 B / 1 D interconnected in series. Due to the stepped embodiment, there is once again a serial interconnection within the subsegments, wherein the upper subcell is in each case connected to the lower subcell via a tunnel diode. Within a subsegment, the segment areas 2A and 2E, 2B and 2F, 2C and 2G as well as 2D and 2H are connected in series. As in FIG. 13, a stepped embodiment is thus provided in which the segment regions of the uppermost semiconductor layer are not connected in parallel or form a single segment region but only in the form of the complete tandem cell present in the sub-segment with the other ones

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Computer Hardware Design (AREA)
  • Physics & Mathematics (AREA)
  • Power Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Sustainable Development (AREA)
  • Photovoltaic Devices (AREA)

Abstract

L'invention concerne une cellule photovoltaïque tolérant l'ajustement, dont le côté avant présente au moins trois segments partiels sur lesquels le rayonnement électromagnétique peut être directement incident. Au moins deux segments partiels se présentent sous la forme d'un premier type de segment et au moins un segment partiel se présente sous la forme d'un deuxième type de segment et ils sont disposés de telle manière que pour le premier et le deuxième type de segment, au moins deux zones de segment séparées sur lesquelles le rayonnement électromagnétique peut être directement incident soient formées. Au moins deux segments partiels du premier type sont connectés en parallèle et/ou sont reliés l'un à l'autre par l'intermédiaire d'une région de transition garantissant le flux de courant latéral et les deux segments partiels du premier type sont en outre connectés en série audit segment partiel du deuxième type. La cellule photovoltaïque peut selon l'invention contenir les régions de segment soit dans une forme de réalisation étagée des régions de segment comprenant au moins deux cellules partielles et/ou dans une forme de réalisation latérale comprenant des régions de segment disposées les unes à côté des autres.
EP13811523.3A 2012-12-21 2013-12-19 Cellule photovoltaïque tolérant l'ajustement Withdrawn EP2936566A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102012025160 2012-12-21
PCT/EP2013/077406 WO2014096200A1 (fr) 2012-12-21 2013-12-19 Cellule photovoltaïque tolérant l'ajustement

Publications (1)

Publication Number Publication Date
EP2936566A1 true EP2936566A1 (fr) 2015-10-28

Family

ID=49876634

Family Applications (1)

Application Number Title Priority Date Filing Date
EP13811523.3A Withdrawn EP2936566A1 (fr) 2012-12-21 2013-12-19 Cellule photovoltaïque tolérant l'ajustement

Country Status (4)

Country Link
US (1) US10205044B2 (fr)
EP (1) EP2936566A1 (fr)
DE (1) DE112013006161A5 (fr)
WO (1) WO2014096200A1 (fr)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2416254B1 (es) 2009-02-09 2014-12-29 Semprius, Inc. Módulos fotovoltaicos de tipo concentrador (cpv), receptores y sub-receptores y métodos para formar los mismos
US20160112001A1 (en) * 2014-10-15 2016-04-21 Emcore Solar Power, Inc. Solar cell assembly comprising solar cells shaped as a portion of a circle
DE102015006379B4 (de) * 2015-05-18 2022-03-17 Azur Space Solar Power Gmbh Skalierbare Spannungsquelle
DE102015007326B3 (de) 2015-06-12 2016-07-21 Azur Space Solar Power Gmbh Optokoppler
WO2017059068A1 (fr) * 2015-09-29 2017-04-06 Semprius, Inc. Architectures de microcellule photovoltaïque multijonction pour récupération d'énergie et/ou conversion de puissance laser
US10418501B2 (en) 2015-10-02 2019-09-17 X-Celeprint Limited Wafer-integrated, ultra-low profile concentrated photovoltaics (CPV) for space applications
DE102016001386A1 (de) * 2016-02-09 2017-08-10 Azur Space Solar Power Gmbh Stapelförmige Mehrfachsolarzelle
US11088294B2 (en) * 2016-06-30 2021-08-10 Byd Company Limited Photovoltaic cell assembly, photovoltaic cell array, and solar cell assembly
WO2018232524A1 (fr) * 2017-06-23 2018-12-27 University Of Ottawa Dispositif photovoltaïque
US20190181289A1 (en) * 2017-12-11 2019-06-13 Solaero Technologies Corp. Multijunction solar cells
CN112038425B (zh) 2019-06-03 2024-04-30 中国科学院苏州纳米技术与纳米仿生研究所 一种多结叠层激光光伏电池
EP4064368A1 (fr) 2021-03-24 2022-09-28 Sunpower Corporation Réseau photovoltaïque croisé

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4278473A (en) 1979-08-24 1981-07-14 Varian Associates, Inc. Monolithic series-connected solar cell
US4249959A (en) * 1979-11-28 1981-02-10 Rca Corporation Solar cell construction
US20070137698A1 (en) * 2002-02-27 2007-06-21 Wanlass Mark W Monolithic photovoltaic energy conversion device
US20060048811A1 (en) * 2004-09-09 2006-03-09 Krut Dimitri D Multijunction laser power converter
DE102004055225B4 (de) 2004-11-16 2014-07-31 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Anordnung mit Solarzelle und integrierter Bypass-Diode
US8742251B2 (en) 2006-12-20 2014-06-03 Jds Uniphase Corporation Multi-segment photovoltaic power converter with a center portion
CA2834131A1 (fr) * 2011-05-02 2012-11-08 Mcmaster University Adaptation de courant de surface de cellules solaires tandems

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2014096200A1 *

Also Published As

Publication number Publication date
DE112013006161A5 (de) 2015-09-10
US20150380591A1 (en) 2015-12-31
US10205044B2 (en) 2019-02-12
WO2014096200A1 (fr) 2014-06-26

Similar Documents

Publication Publication Date Title
WO2014096200A1 (fr) Cellule photovoltaïque tolérant l'ajustement
EP3378104B1 (fr) Cellule solaire comprenant plusieurs absorbeurs reliés entre eux par des contacts sélectifs porteurs de charge
DE3615515C2 (fr)
DE3047431C2 (de) Solarzelle mit mehreren übereinander angeordneten pn-Übergängen für Konzentratoranwendung
DE2607005C2 (de) Integrierte Tandem-Solarzelle
DE4213391A1 (de) Monolithische tandem-solarzelle
DE202011101552U1 (de) Gitterdesign für eine III-V-Verbindungshalbleiterzelle
DE10297371T5 (de) Vorrichtung und Verfahren für eine integrale Bypassdiode in Solarzelle
EP3012874B1 (fr) Cellule solaire à jonctions multiples intégrée en forme de pile
WO2018134016A1 (fr) Cellule solaire multiple avec sous-cellule au germanium au dos et son utilisation
EP2289107B1 (fr) Cellule solaire et procédé de fabrication
WO2016150878A1 (fr) Cellule solaire photovoltaïque
EP3018718A1 (fr) Piles de cellules solaires
DE202023101309U1 (de) Solarzelle und Photovoltaikmodul
WO2013050563A2 (fr) Composant à semi-conducteurs présentant une structure multicouche et module formé à partir de ce composant
DE102016116192B3 (de) Photovoltaikmodul mit integriert serienverschalteten Stapel-Solarzellen und Verfahren zu seiner Herstellung
DE102015013514B4 (de) Optischer Empfängerbaustein
DE102011118473A1 (de) Solarzelle
DE102011081983A1 (de) Solarzelle und Verfahren zu ihrer Herstellung
DE69920608T2 (de) Solarzellenbatterie
WO1998047184A1 (fr) Procede de fabrication d'un systeme de cellules photovoltaiques individuelles disposees en serie, et le systeme en question
DE102018123485B4 (de) Verfahren zum Auftrennen eines Halbleiterbauelements mit einem pn-Übergang
DE202015106374U1 (de) Photovoltaikmodul
DE102012223698A1 (de) Konzentratorsystem
DE4143083A1 (de) Solarzelle

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20150720

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20190709

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20210701