Storage battery

Abstract

A storage battery is provided in which an expand grid is improved with respect to the widths of grid wires 1 b , the sectional areas of nodes 1 e , and the shapes of meshes 1 c , whereby the productivity of the expand grid can be enhanced and the life performance can be improved. As means for attaining the object, a storage battery in which an expand grid is used as a battery plate, the expand grid being a grid member which is formed by expanding a side portion of a collector frame portion 1 a of a metal sheet 1 to connect a large number of grid wires 1 b to one another in a net-like shape, is configured so that widths of grid wires 1 b of a row which is directly connected to the collector frame portion 1 a of the expand grid, and a lateral end row are larger than widths of grid wires 1 b of at least one of intermediate rows.

What is claimed is:  
     
         1 . A storage battery in which an expand grid is used as a battery plate, said expand grid being a grid member which is formed by expanding a side portion of a collector frame portion of a metal sheet to connect a large number of grid wires to one another in a net-like shape, wherein 
 widths of grid wires of a row which is directly connected to said collector frame portion of said expand grid, and a lateral end row are larger than widths of grid wires of at least one of intermediate rows.    
     
     
         2 . A storage battery according to  claim 1 , wherein the widths of said grid wires of said row which is directly connected to said collector frame portion are largest, and the widths of said grid wires of said lateral end row are smaller than the widths of said grid wires of said row which is directly connected to said collector frame portion, and larger than the widths of said grid wires of at least one of said intermediate rows excluding said row which is directly connected to said collector frame portion, and said lateral end row.  
     
     
         3 . A storage battery according to  claim 1  or  2 , wherein the largest grid wire width is not smaller than 1.2 times and not larger than 1.6 times the smallest grid wire width.  
     
     
         4 . A storage battery in which an expand grid is used as a battery plate, said expand grid being a grid member which is formed by forming a large number of rows of slits that are intermitted at regular intervals in a metal sheet to arrange intermittent portions of said slits in a zigzag manner, and stretching said metal sheet in a width direction to expand said metal sheet, to connect grid wires to one another in a net-like shape via nodes configured by said intermittent portions, said grid wires being formed between slits that are adjacent to each other in the width direction, wherein 
 in each of said nodes, a node sectional area of a maximum section along a cutting plane of said slits is two or more times a grid wire sectional area of a section of each of said grid wires, the section being perpendicular to a longitudinal direction of said grid wire.    
     
     
         5 . A storage battery according to  claim 4 , wherein each of meshes surrounded by said grid wires which are connected to one another in a net-like shape via said nodes has an area of 70 mm 2  or more.  
     
     
         6 . A storage battery according to  claim 4  or  5 , wherein the grid wire sectional area is not smaller than 1.0 mm 2  and not larger than 3.5 mm 2 .  
     
     
         7 . A storage battery in which an expand grid is used as a battery plate, said expand grid being a grid member which is formed by forming a large number of slits in a metal sheet in a zigzag manner, and stretching said metal sheet in a width direction to expand said slits into meshes, thereby connecting four grid wires surrounding each of said meshes to one another in a net-like shape, wherein 
 opposed ones of said four grid wires surrounding each of said meshes have a substantially same length, and a length of two opposed ones of said grid wires is not smaller than 102% of and not larger than 120% of a length of other two opposed ones of said grid wires.