SOLAR MODULE SERIALLY CONNECTED IN THE FRONT

• US 20100089435A1
• Filed: 03/07/2008
• Published: 04/15/2010
• Est. Priority Date: 03/08/2007
• Status: Active Grant

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: Lockenhoff, Rudiger
• Granted Patent: US 8,704,085 B2
• Time in Patent Office: Days
• US Class Current: 136/246
• CPC Class Codes: B64G 1/443 Photovoltaic cell arrays
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 27/1421 comprising bypass diodes integrated or directly associated with the device, e.g. bypass diode integrated or formed in or on the same substrate as the solar cell
• CPC Class Codes: H01L 31/0475 PV cell arrays made by cells in a planar, e.g. repetitive, configuration on a single semiconductor substrate; PV cell microarrays PV modules composed of a plurality of thin film solar cells deposited on the same substrate H01L31/046
• CPC Class Codes: H01L 31/048 Encapsulation of modules
• CPC Class Codes: H01L 31/0504 specially adapted for series or parallel connection of solar cells in a module
• CPC Class Codes: H01L 31/052 Cooling means directly associated or integrated with the PV cell, e.g. integrated Peltier elements for active cooling or heat sinks directly associated with the PV cells cooling means in combination with the PV module H02S40/42
• CPC Class Codes: H01L 31/0687 Multiple junction or tandem solar cells
• CPC Class Codes: Y02E 10/544 Solar cells from Group III-V materials
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

The present invention shows a solar cell element comprising a semiconductor substrate layer (2) with precisely one first doping, a layer structure (1) which is disposed on the front-side of the substrate layer (2) and is adjacent to the substrate layer, said layer structure having at least one doping complementary to the first doping, a rear-side metallisation (3) which is disposed on the rear-side of the substrate layer which is situated opposite the layer structure (1) and is adjacent to the substrate layer, and a first (4) and a second (6) front-side metallisation, the first front-side metallisation (4) contacting the layer structure (1) electrically and the second front-side metallisation (6), electrically insulated from the first front-side metallisation and the layer structure (1), being disposed on the front-side of the substrate layer adjacent to the substrate layer.

Claims

1-36. -36. (canceled)

37. A solar cell module comprising at least two series-connected solar cell elements which are disposed respectively with a rear-side metallization on a carrier structure, the electrical contacting of the series connection of at least two of the series-connected solar cell elements being configured exclusively on a front-side of these solar cell elements which is situated opposite the carrier structure, at least one of the at least two solar cell elements connected on the front-side having:

a supporting semiconductor layer with only one first type of doping;

a layer structure which is disposed on a front-side of the supporting semiconductor layer adjacent to the supporting semiconductor layer and which has at least one doping complementary to the first doping;

the rear-side metallization being disposed on the rear-side of the supporting semiconductor layer which is situated opposite the layer structure, adjacent to the supporting semiconductor layer;

a first front-side metallization and a second front-side metallization, the first front-side metallization contacting the layer structure electrically, and the second front-side metallization being spaced from the first front-side metallization and the layer structure on the front-side of the supporting semiconductor layer adjacent to the supporting semiconductor layer such that, between the second front-side metallization and the rear-side metallization, only the supporting semiconductor layer is situated.

38. A solar cell module according to claim 37 wherein at least one of:

the supporting semiconductor layer;

the rear-side metallization; and

the second front-side metallization is at least one of;

disposed such that the electrical contacting of the rear-side metallization to the second front-side metallization through the supporting semiconductor layer has a surface-specific resistance of less than 10<sup>−

2</sup> Ω

cm²; and

configured such that the electrical contacting of the rear-side metallization to the second front-side metallization through the supporting semiconductor layer has a surface-specific resistance of less than 10<sup>−

2</sup> Ω

cm².

39. A solar cell module according to claim 38 wherein the surface-specific resistance is less than 10⁻

3 Ω

cm².

40. A solar cell module according to claim 39 wherein the surface-specific resistance is less than 5×

10<sup>−

4</sup> Ω

cm².

41. A solar cell module according to claim 37 wherein the rear-side metallization at least one of:

viewed in the layer plane, extends from the second front-side metallization up to the first front-side metallization;

is a flat, unstructured metallization; and

,

is a flat, structured metallization.

42. A solar cell module according to claim 37 further comprising a carrier structure which is disposed on the rear-side metallization side and has at least one of:

a cooling plate;

a cooling plate with a non-metallic front; and

, a cooling plate with a ceramic front.

43. A solar cell module according to claim 42 wherein the cooling plate is configured as at least one of:

a structure-supporting part of an active water cooling body; and

, a structure-supporting part made of ceramic of an active water cooling body.

44. A solar cell module according to claim 42 wherein at least one of:

the carrier structure has an electrically non-conductive layer which is disposed between the cooling plate and at least one of the rear-side metallization, an adhesive layer and a ceramic layer; and

, the carrier structure has an electrical conductor structure which is disposed between the cooling plate and the rear-side metallization.

45. A solar cell module according to claim 44 wherein the electrical conductor structure has at least one of a conductive adhesive layer and a solder layer on the rear-side metallization side and a strip conductor structure on the cooling plate side.

46. A solar cell module according to claim 37 further comprising a cell connector which contacts the two solar cell elements on their front-sides.

47. A solar cell module according to claim 46 wherein the cell connector is configured as a wire.

48. A solar cell module according to claim 46 wherein the cell connector connects electrically the first front-side metallization of the first of the solar cell elements connected on the front-side to the second front-side metallization of the second of the solar cell elements connected on the front-side.

49. A solar cell module according to claim 46 wherein the cell connector comprises a wire which comprises at least one of gold, silver and aluminium.

50. A solar cell module according to claim 37 wherein a bypass diode with reversed polarity is connected in parallel to at least one of the solar cell elements.

51. A solar cell module according to claim 50 wherein a bypass diode with reversed polarity is connected in parallel to each solar cell element.

52. A solar cell module according to claim 50 wherein at least one of the solar cell elements together with the bypass diode has a common portion of the supporting semiconductor layer.

53. A solar cell module according to claim 50 wherein at least one of the bypass diodes on the front-side thereof oriented away from the carrier structure has a first front-side metallization and a second front-side metallization spaced from the first front-side metallization.

54. A solar cell module according to claim 50 wherein at least one of the bypass diodes has a supporting semiconductor layer with a first doping, a layer structure which is disposed on the front-side of the supporting semiconductor layer which is oriented away from the carrier structure and is adjacent to the supporting semiconductor layer, said layer structure having at least one doping complementary to the first doping, and a rear-side metallization which is disposed on the rear-side of the supporting semiconductor layer which is situated opposite the layer structure and is adjacent to the supporting semiconductor layer.

55. A solar cell module according to claim 53 wherein, in the case of the at least one bypass diode, the first front-side metallization contacts the layer structure electrically, and the second front-side metallization, electrically insulated from the first front-side metallization and the layer structure, is disposed on the front-side of the supporting semiconductor layer adjacent to the supporting semiconductor layer.

56. A solar cell module according to claim 54 wherein, in the case of the at least one bypass diode, the first front-side metallization contacts the layer structure electrically, and the second front-side metallization, electrically insulated from the first front-side metallization and the layer structure, is disposed on the front-side of the supporting semiconductor layer adjacent to the supporting semiconductor layer.

57. A solar cell module according to claim 53 wherein at least one of the solar cell elements on the front-side of the supporting semiconductor layer which is oriented away from the carrier structure and adjacent to said semiconductor layer has a metallic front-side contact which is insulated electrically from the front-side metallizations and the layer structure and is connected electrically to the first front-side metallization of the bypass diode via a cell connector.

58. A solar cell module according to claim 50 wherein the electrical connection of the solar cell elements and the bypass diodes is configured exclusively on the front-side which is oriented away from the carrier structure.

59. A solar cell module according to claim 58 wherein the electrical connection is configured via cell connectors.

60. A solar cell module according to claim 37 wherein the supporting semiconductor layer has a thickness of less than 200 μ

m.

61. A solar cell module according to claim 37 further comprising at least one of a germanium layer, a p-doped germanium layer, a gallium arsenide layer and a silicon layer as supporting semiconductor layer.

62. A solar cell module according to claim 37 wherein the semiconductor structure having the supporting semiconductor layer and the layer structure is monocrystalline and has at least two photoelectrically active p-n junctions having different band gaps.

63. A solar cell module according to claim 37 wherein at least one of:

at least one of the first front-side metallization and the second front-side metallization has an alloyed metal layer structure; and

,

at least one of the first front-side metallization and the second front-side metallization is configured in the form of at least one of a continuous layer structure and a plurality of non-continuous islands.

64. A solar cell module according to claim 37 wherein, viewed in the layer plane, the ratio of the surface area proportion of the second front-side metallization and of the surface area proportion of the layer structure is less than 0.1.

65. A solar cell module according to claim 64 wherein the ratio is less than 0.05.

66. A solar cell module according to claim 65 wherein the ratio is less than 0.01.

67. A solar cell module according to claim 66 wherein the ratio is less than 0.005.

68. A solar cell module according to claim 67 wherein the ratio is less than 0.002.

69. A solar cell module according to claim 37 wherein at least one of:

the second front-side metallization has precisely one continuous metallization surface; and

, the second front-side metallization has at least two continuous metallization surfaces which are disposed at a spacing from each other.

70. A solar cell module according to claim 37 wherein the first doping is one of a p-doping and an n-doping.

71. A solar cell module according to claim 37 further comprising a parallel connection of at least two series connections of solar cell elements, each said series connections of solar cell elements having at least two series-connected solar cell elements connected on the front-side.

72. A solar cell module according to the preceding claim 71 wherein each solar cell element of one series connection is connected in parallel to a solar cell element of at least another series connection.

73. A solar cell module according to claim 37 wherein, viewed in the layer plane, at least two of the solar cell elements have at least one of different total surface areas and different surface areas of their layer structures.

74. A solar cell module according to claim 37 further comprising at least one of an encapsulation disposed on the front-side and a transparent plate which has a transparent filling compound applied as encapsulation.

75. A solar cell module according to claim 74 wherein the filling compound comprises at least one of silicone and a glass plate.

79. Use of a solar cell module according to claim 37 in a concentrator arrangement.

76. A method for the production of a solar cell module, wherein at least two solar cell elements respectively with their rear-side metallizations being disposed on a carrier structure and being connected in series, the electrical contacting at least of two of the solar cell elements being configured exclusively on a front-side of these solar cell elements which is situated opposite the carrier structure, and at least one of the solar cell elements having a supporting semiconductor layer with precisely one first type of doping, a layer structure which is disposed on the front-side of the supporting semiconductor layer adjacent to the supporting semiconductor layer, said layer structure having a doping complementary to the first doping, a rear-side metallization which is disposed on the rear-side of the supporting semiconductor layer which is situated opposite the layer structure and is adjacent to the supporting semiconductor layer, and first and second front-side metallizations, the first front-side metallization contacting the layer structure electrically, and the second front-side metallization being spaced from the first front-side metallization and the layer structure on the front-side of the supporting semiconductor layer adjacent to the supporting semiconductor layer such that, between the second front-side metallization and the rear-side metallization, exclusively the supporting semiconductor layer is situated as the electrical contacting, in that all the individual elements for a solar cell element are configured respectively repeatedly on a supporting semiconductor layer, and wherein thereafter the supporting semiconductor layer together with the repeatedly configured individual elements on the side which is orientated away from the front-side are at least one of glued and soldered on a carrier structure, and wherein thereafter the multiple solar cell elements are separated from the supporting semiconductor layer which is applied on the carrier structure and wherein finally the individual solar cell elements are connected to each other electrically.

78. The method according to claim 76 wherein separating comprises at least one of sawing, sawing using a chip saw, wet chemical etching, dry chemical etching and laser cutting.

77. A method for the production of a solar cell module, wherein at least two solar cell elements respectively with their rear-side metallizations being disposed on a carrier structure and being connected in series, the electrical contact at least of two of the solar cell elements being configured exclusively on the front-side of these solar cell elements which is situated opposite the carrier structure, and at least one of the solar cell elements having a supporting semiconductor layer, which forms an electrical contacting, with precisely one first type of doping, a layer structure which is disposed on the front-side of the supporting semiconductor layer adjacent to the supporting semiconductor layer, said layer structure having at least one doping complementary to the first doping, a rear-side metallization which is disposed on the rear-side of the supporting semiconductor layer which is situated opposite the layer structure and is adjacent to the supporting semiconductor layer, and first and second front-side metallizations, the first front-side metallization contacting the layer structure electrically, and the second front-side metallization, electrically insulated from the first front-side metallization and the layer structure, being disposed on the front-side of the supporting semiconductor layer adjacent to the supporting semiconductor layer such that, between the second front-side metallization and the rear-side metallization, exclusively the supporting semiconductor layer is situated as the electrical contacting, wherein all the individual elements for a solar cell element are configured respectively repeatedly on a supporting semiconductor layer, and wherein thereafter the front-side metallization at least of two different solar cell elements which are still to be separated is connected electrically via cell connectors, and wherein thereafter, on the front-side, at least one of a transparent filling compound and silicone is applied, and wherein thereafter at least one of a transparent plate and a glass plate is applied on the side of the filling compound, which is orientated away from the substrate layer, on said filling compound, and wherein thereafter the multiple solar cell elements are separated from the supporting semiconductor layer which is applied on the carrier structure wherein, from the side, which is oriented away from the plate, between the solar cell elements which are still to be separated, gaps are introduced up to at least the filling compound and wherein finally the supporting semiconductor layer together with the separated solar cell elements is at least one of glued and soldered on the side thereof which is oriented away from the front-side onto a carrier structure.