Production of separator comprising polyolefin resin fibre nonwoven cloth including a sulphonation process giving an even and higher degree of sulphonation on the surface of the nonwoven cloth. The sulphonation process comprises passing the nonwoven cloth t...

Spirally-rolled electrodes for batteries wherein the electrodes having a concentric circle shape or an elliptic shape with positive electrode and negative electrode wound spirally via a separator therebetween has the characteristics as below: (1) the posit...

An electrode substrate is formed by mechanically processing a nickel foil so as to be made three dimensional through the creation of concave and convex parts, and then, this substrate is filled with active material or the like so that an electrode is manuf...