Electrolyte-solution filling method and battery structure of lithium secondary battery

A method for filling an electrolyte solution for a lithium secondary battery comprising a pipe as a body member of a case for the battery, an internal electrode body formed by winding a positive electrode, and a negative electrode, with a separator sandwiched therebetween around an outer periphery of a core, and an electrolyte solution to impregnate said internal electrode, which comprises the steps of:

• caulking first and second ends of said pipe so as to seal the case for the battery;
• inserting through a first end of said battery a tip of a nozzle for injecting said electrolyte solution in such a depth that said tip at least reaches a position on an end surface of said internal electrode body located on an opposite side of said internal electrode body relative to said first end of said battery, said tip being inserted through a through hole of said core, and through an electrolyte solution injection opening provided in an extended position of said through hole on said first end of the battery, or an electrolyte solution injection opening integrally formed with an external terminal in an extended position of the trough hole of the core on said first end of the battery;
• after said caulking, injecting the electrolyte solution until at least the internal electrode body is immersed;
• and
• thereafter exacting a portion of said electrolyte solution from inside the battery by using a nozzle for extraction of electrolyte solution.