Nonaqueous electrolyte secondary cells and process for fabricating same

摘要

A nonaqueous electrolyte secondary cell includes a rolled-up electrode unit composed of a positive electrode, a negative electrode and a separator interposed therebetween, and a negative electrode current collector plate and a positive electrode current collector plate joined to the respective ends of the electrode unit. The negative electrode collector plate is joined to an edge of the negative electrode projecting at one of the opposite ends of the electrode unit. The collector plate has a two-layer structure of a copper layer made of copper or an alloy consisting predominantly of copper, and a metal layer made of a metal not forming an intermetallic compound with lithium and having a lower laser beam reflectivity than copper or an alloy consisting predominantly of the metal. The collector plate has its copper layer contacted with the edge of the negative electrode and welded thereto with a laser beam.