Shingled solar cell module

Abstract

A high efficiency configuration for a solar cell module comprises solar cells arranged in a shingled manner to form super cells, which may be arranged to efficiently use the area of the solar module, reduce series resistance, and increase module efficiency.

What is claimed is: 
     
         1 . A method comprising:
 forming a super cell comprising a series connected string of at least N≧25 solar cells on a same backing, each solar cell having a breakdown voltage greater than about 10 volts and arranged with long sides of adjacent solar cells overlapping and conductively bonded with an adhesive; and   connecting each super cell with at most a single bypass diode   
     
     
         2 . A method as in  claim 1  wherein N is greater than or equal to 30. 
     
     
         3 . A method as in  claim 1  wherein N is greater than or equal to 50. 
     
     
         4 . A method as in  claim 1  wherein N is greater than or equal to 100. 
     
     
         5 . A method as in  claim 1  wherein the adhesive has a thickness less than or equal to about 0.1 mm, and has a thermal conductivity greater than or equal to about 1.5 w/m/k. 
     
     
         6 . A method as in  claim 1  wherein the solar cells are silicon solar cells. 
     
     
         7 . A method as in  claim 1  wherein the super cell has a length in a direction of current flow of at least about 500 mm. 
     
     
         8 . A method as in  claim 1  wherein a first solar cell of the super cell has chamfered corners and a second solar cell of the super cell lacks chamfered corners, and the first solar cell and the second solar cell have a same area exposed to light. 
     
     
         9 . A method as in  claim 1  further comprising confining a spreading of the adhesive utilizing a feature on a solar cell surface. 
     
     
         10 . A method as in  claim 9  wherein the feature comprises a raised feature. 
     
     
         11 . A method as in  claim 9  wherein the feature comprises metallization. 
     
     
         12 . A method as in  claim 11  wherein the metallization comprises a line running a full length of the first long side, at least one contact pad located between the line and the first long side. 
     
     
         13 . A method as in  claim 12  wherein:
 the metallization further comprises fingers electrically connected to the at least one contact pad and running perpendicularly to the first long side; and 
 the conductive line interconnects the fingers. 
 
     
     
         14 . A method as in  claim 9  wherein the feature is on a front side of the solar cell. 
     
     
         15 . A method as in  claim 9  wherein the feature is on a back side of the solar cell. 
     
     
         16 . A method as in  claim 9  wherein the feature comprises a recessed feature. 
     
     
         17 . A method as in  claim 9  wherein the feature is hidden by an adjacent solar cell of the super cell. 
     
     
         18 . A method as in  claim 1  further comprising forming another super cell on the same backing. 
     
     
         19 . A method as in  claim 1  further comprising:
 conductively bonding to a surface of a solar cell, a flexible electrical interconnect having a long axis parallel to a second direction perpendicular to the first direction; and 
 causing the flexible electrical interconnect to accommodate thermal expansion of the solar cell in two dimensions 
 
     
     
         20 . A method as in  claim 19  wherein the flexible electrical interconnect has a thickness less than or equal to about 100 microns to provide a resistance of less than or equal to about 0.012 Ohms. 
     
     
         21 . A method as in  claim 19  wherein the surface comprises a back surface. 
     
     
         22 . A method as in  claim 19  further comprising contacting another super cell with the flexible electrical interconnect. 
     
     
         23 . A method as in  claim 22  wherein the other super cell is in line with the super cell. 
     
     
         24 . A method as in  claim 22  wherein the other super cell is adjacent to the super cell. 
     
     
         25 . A method as in  claim 19  further comprising folding a first portion of the interconnect around an edge of the super cell such that a remaining second interconnect portion is on a backside of the super cell. 
     
     
         26 . A method as in  claim 19  further comprising electrically connecting the flexible electrical interconnect to a bypass diode. 
     
     
         27 . A method as in  claim 1  further comprising:
 arranging a plurality of super cells in two or more parallel rows on the same backing to form a solar module front surface, wherein the backing sheet is white and comprises darkened stripes of location and width corresponding to gaps between super cells. 
 
     
     
         28 . A method as in  claim 1  further comprising connecting at least one pair of cell strings to a power management system. 
     
     
         29 . A method as in  claim 1  further comprising:
 electrically connecting a power management device with the super cell; 
 causing the power management device to receive a voltage output of the super cell; 
 based upon the voltage, causing the power management device to determine if a solar cell is in reverse bias; and 
 causing the power management device to disconnect the solar cell in reverse bias from a super cell module circuit 
 
     
     
         30 . A method as in  claim 1  wherein the super cell is disposed on the backing to form a first module having a top conductive ribbon on first side facing a direction of solar energy, the method further comprising:
 disposing another super cell on another backing to form a second module having a bottom ribbon on a second side facing a direction away from the direction of the solar energy, 
 wherein the second module overlaps and is bonded to a portion of the first module including the top ribbon. 
 
     
     
         31 . A method as in  claim 30  wherein the second module is bonded to the first module by adhesive. 
     
     
         32 . A method as in  claim 30  wherein the second module is bonded to the first module by a mating arrangement. 
     
     
         33 . A method as in  claim 30  further comprising overlapping a junction box with the second module. 
     
     
         34 . A method as in  claim 33  wherein the second module is bonded to the first module by a mating arrangement. 
     
     
         35 . A method as in  claim 34  wherein the mating arrangement is between the junction box and another junction box on the second module. 
     
     
         36 . A method as in  claim 30  wherein the backing comprises glass. 
     
     
         37 . A method as in  claim 30  wherein the backing comprises other than glass. 
     
     
         38 . A method as in  claim 30  further comprising:
 electrically connecting a relay switch in series between the first module and the second module; 
 sensing an output voltage of the first module by a controller; and 
 activating the relay switch with the controller where the output voltage falls below a limit. 
 
     
     
         39 . A method as in  claim 1  wherein the solar cell comprises a chamfered portion cut from a larger piece. 
     
     
         40 . A method as in  claim 39  wherein forming the super cell comprises placing a long side of the solar cell in electrical contact with a long side of similar length of another solar cell having a chamfered portion.