Electrode group for nonaqueous battery and method for producing the same, and cylindrical nonaqueous secondary battery and method for producing the same

An electrode group for a nonaqueous battery comprising:

• a positive electrode and a negative electrode wound with a porous insulator interposed therebetween, wherein
• the positive electrode includes
• a double-coated part which includes a positive electrode active material layer formed on each surface of a positive electrode current collector core;
• and
• a core exposed part which is located at a longitudinal center of the positive electrode current collector core, and does not include the positive electrode active material layer,
• a positive electrode current collector lead is connected to the core exposed part of the positive electrode,
• the negative electrode includes
• a double-coated part which includes a negative electrode active material layer formed on each surface of a negative electrode current collector core;
• a core exposed part which is located at an end of the negative electrode current collector core, and does not include the negative electrode active material layer;
• and
• a single-coated part which is located between the double-coated part and the core exposed part, and includes the negative electrode active material layer formed only on one of the surfaces of the current collector core of the negative electrode,
• a plurality of grooves are formed in each surface of the double-coated part of the negative electrode to be inclined relative to a longitudinal direction of the negative electrode, while the grooves are not formed in the single-coated part of the negative electrode,
• a negative electrode current collector lead is connected to the core exposed part of the negative electrode, and
• the negative electrode is wound in such a manner that the core exposed part of the negative electrode constitutes a last wound end.