High efficiency configuration for solar cell string

Abstract

A high efficiency configuration for a string of solar cells comprises series-connected solar cells arranged in an overlapping shingle pattern. Front and back surface metallization patterns may provide further increases in efficiency.

1 - 20 . (canceled) 
     
     
         21 . A solar device comprising:
 a first solar cell having a front surface, a back surface, and an electrically conductive front surface metallization on the front surface; and   a second solar cell having a front surface, a back surface, and an electrically conductive back surface metallization on the back surface, wherein   a first front edge of the front surface of the first solar cell is overlapped by a first back edge of the back surface of the second solar cell,   the front surface metallization of the first solar cell comprises:
 a bus contact that is overlapped by the first back edge of the back surface of the second solar cell, the bus contact including a bus bar or a plurality of contact pads, 
 a plurality of fingers that are electrically connected to the bus contact and that extend away from the bus contact towards a second front edge of the front surface of the first solar cell that opposes the first front edge, 
 one or more bypass conductors that interconnect two or more of the fingers to provide multiple current paths between the fingers and the bus contact, and 
 one or more end conductors that interconnect two or more of the fingers to provide additional current paths between the fingers and the bus contact. 
   
     
     
         22 . The solar device of  claim 21 , wherein the one or more bypass conductors and the one or more end conductors are structured to electrically bypass cracks that form in the front surface metallization of the first solar cell. 
     
     
         23 . The solar device of  claim 21 , wherein:
 the first and second solar cells are rectangular or substantially rectangular and include two oppositely positioned long sides and two oppositely positioned short sides; and   the first front edge of the front surface of the first solar cell and the first back edge of the back surface of the second solar cell are respective edges of the long sides of the first and second solar cells.   
     
     
         24 . The solar device of  claim 21 , wherein the bus contact of the first solar cell is bonded to the back surface metallization of the second solar cell with an electrically conductive material that includes an electrically conductive film, electrically conductive paste, electrically conductive tape, electrically conductive adhesive, electrically conductive solder bond, or electrically conductive solder. 
     
     
         25 . The solar device of  claim 21 , wherein the back surface metallization of the second solar cell comprises a bus contact that includes a bus bar or a plurality of contact pads aligned with and conductively bonded to the bus contact of the front surface metallization pattern of the first solar cell. 
     
     
         26 . The solar device of  claim 21 , wherein the front surface of the second solar cell includes a front surface metallization and a mechanically compliant electrical interconnect conductively bonded to the front surface metallization of the second solar cell. 
     
     
         27 . The solar device of  claim 26 , wherein the mechanically compliant electrical interconnect is electrically connected to a bypass diode. 
     
     
         28 . The solar device of  claim 21 , wherein the bypass conductor is spaced apart from the bus contact by less than or equal to about 5 millimeters. 
     
     
         29 . The solar device of  claim 21 , wherein the bypass conductor is spaced apart from the bus contact by less than or equal to about 2.5 millimeters. 
     
     
         30 . The solar device of  claim 21 , wherein the bypass conductor is spaced apart from the bus contact by less than or equal to about 1.0 millimeters. 
     
     
         31 . The solar device of  claim 21 , wherein the front surface metallization of the first solar cell comprises, of the one or more bypass conductors, first and second bypass conductors that interconnect two or more of the fingers and provide multiple current paths between first and second fingers and the bus contact. 
     
     
         32 . The solar device of  claim 21 , wherein the front surface metallization of the first solar cell forms two or more rectangular regions on the front surface of the first solar cell such that portions of the bus contact, the one or more bypass conductors, the end conductor, and the two or more of the fingers are sides of the rectangular regions. 
     
     
         33 . The solar device of  claim 32 , wherein the two or more rectangular regions abut each other and extend in line with each other away from the bus contact in line with the fingers. 
     
     
         34 . The solar device of  claim 33 , wherein the two or more rectangular regions have a common width with respect to short axes thereof and different lengths with respect to long axes thereof. 
     
     
         35 . The solar device of  claim 21 , wherein the bus contact extends parallel to a long axis of the first solar cell and the fingers extend perpendicularly away from the bus contact. 
     
     
         36 . The solar device of  claim 21 , wherein the bus contact is arranged proximate the first front edge of the first solar cell, the end conductor is arranged proximate the second front edge of the first solar cell, and the one or more bypass conductors are arranged between the bus contact and the end conductor along one or more of the fingers. 
     
     
         37 . The solar device of  claim 21 , wherein the bypass conductors, the fingers, and the end conductors have a common width. 
     
     
         38 . The solar device of  claim 21 , wherein the bypass conductors are formed along a straight line and do not interconnect all of the fingers. 
     
     
         39 . A solar device comprising:
 a first solar cell having a front surface, a back surface, and an electrically conductive front surface metallization on the front surface; and   a second solar cell having a front surface, a back surface, and an electrically conductive back surface metallization on the back surface, wherein   a first front edge of the front surface of the first solar cell is overlapped by a first back edge of the back surface of the second solar cell,   the front surface metallization of the first solar cell comprises:
 a bus contact that is overlapped by the first back edge of the back surface of the second solar cell, the bus contact including a bus bar or a plurality of contact pads, 
 fingers that are electrically connected to the bus contact and that extend away from the bus contact towards a second front edge of the front surface of the first solar cell that opposes the first front edge, 
 a bypass conductor that interconnects a first finger of the fingers to a second finger of the fingers to provide multiple current paths between the first and second fingers and the bus contact, 
 an end conductor that interconnects the first and second fingers to a third finger of the fingers to provide an additional current path between fingers and the bus contact, and 
 the bypass conductor, the fingers, and the end conductor are structured to electrically bypass cracks that form in the front surface metallization of the first solar cell. 
   
     
     
         40 . A solar device comprising:
 a first solar cell having a front surface, a back surface, and an electrically conductive front surface metallization on the front surface; and   a second solar cell having a front surface, a back surface, and an electrically conductive back surface metallization on the back surface, wherein   a first front edge of the front surface of the first solar cell is overlapped by a first back edge of the back surface of the second solar cell,   the front surface metallization of the first solar cell comprises:
 a bus contact that is overlapped by the first back edge of the back surface of the second solar cell, the bus contact including a bus bar or a plurality of contact pads, 
 fingers that are electrically connected to the bus contact and that extend away from the bus contact towards a second front edge of the front surface of the first solar cell that opposes the first front edge, 
 a bypass conductor that interconnects a first finger of the fingers to a second finger of the fingers to provide multiple current paths between the first and second fingers and the bus contact, 
 an end conductor that interconnects the first and second fingers to a third finger of the fingers to provide an additional current path between fingers and the bus contact, and 
 the bypass conductor, the first and second fingers, and the end conductor are structured to form at least first and second rectangular shapes, such that the first and second rectangular shapes have a common width with respect to short sides thereof and different lengths with respect to long sides thereof.