Solar cell and solar cell module

Abstract

A solar cell includes: a semiconductor substrate on which at least pn junctions are formed; a multiplicity of finger electrodes that are formed in a comb-like shape on at least one surface of the semiconductor substrate; and a plurality of bus bar electrodes that are arranged so as to be orthogonal to the lengthwise direction of the finger electrodes and are connected with the finger electrodes. This solar cell is configured so that the finger electrodes connected with one of the bus bar electrodes are separated from the finger electrodes connected with another bus bar electrode that is arranged so as to be parallel to this one of the bus bar electrodes, and ends in the lengthwise direction of adjacent two or more of the finger electrodes connected with each bus bar electrode are electrically connected with one another by auxiliary electrodes.

1 . A solar cell comprising a semiconductor substrate having at least a pn junction formed therein, a multiplicity of finger electrodes which are formed in comb shape on at least one surface of the semiconductor substrate, and a plurality of bus bar electrodes which extend orthogonal to the longitudinal direction of the finger electrodes and are connected to the finger electrodes, wherein
 first finger electrodes which are connected to a first bus bar electrode are spaced apart from second finger electrodes which are connected to a second bus bar electrode extending parallel with the first bus bar electrode, and longitudinal ends of adjacent two or more of the finger electrodes connected to each bus bar electrode are electrically connected together by an auxiliary electrode.   
     
     
         2 . The solar cell of  claim 1  wherein longitudinal ends of adjacent two to four of the finger electrodes connected to each bus bar electrode are connected together by an auxiliary electrode. 
     
     
         3 . The solar cell of  claim 1  wherein all adjacent longitudinal ends of the finger electrodes connected to each bus bar electrode are connected together by an auxiliary electrode. 
     
     
         4 . The solar cell of  claim 1  wherein the finger electrodes project from the bus bar electrode to which they are connected, in opposite directions orthogonal to the bus bar electrode, and at each of the opposite ends of the finger electrodes projecting from the bus bar electrode, longitudinal ends of adjacent finger electrodes are electrically connected together by an auxiliary electrode. 
     
     
         5 . The solar cell of  claim 1  wherein at a position other than the longitudinal end of the finger electrodes, adjacent finger electrodes connected to a common bus bar electrode are electrically connected by another auxiliary electrode extending orthogonal to the longitudinal direction of the finger electrodes. 
     
     
         6 . The solar cell of  claim 5  wherein 1 to 10 auxiliary electrodes are provided at a position other than the longitudinal end of the finger electrodes. 
     
     
         7 . The solar cell of  claim 1  wherein the finger electrode has a width of 30 to 120 μm. 
     
     
         8 . The solar cell of  claim 1  wherein the auxiliary electrode has a width of 30 to 500 μm. 
     
     
         9 . A solar cell module comprising a plurality of solar cells as set forth in  claim 1  wherein their bus bar electrodes are connected in series.