| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery capable of outputting a high voltage steadily for a long time, featuring high battery capacity, high energy density, and excellent charging/discharging cycle characteristics, and capable of suppressing separation of a negative electrode active material layer from a negative electrode collector, resulting collection reduction, and deformation of the negative electrode. <P>SOLUTION: The negative electrode 12 is equipped with a negative electrode collector 12a, a protrusion 20 extending from the surface of the negative electrode collector 12a to the outside thereof, and a negative electrode active material layer 12b containing a negative electrode active material and provided at least on the top surface among surfaces of the protrusion 20. A separation propagation preventing part 21 is provided at least a part of the surface of the protrusion 20 to prevent separation of the negative electrode active material layer 12b from the surface of the protrusion due to shrinkage or expansion of the negative electrode active material. This negative electrode 12 is used to manufacture a lithium ion secondary battery. <P>COPYRIGHT: (C)2008,JPO&INPIT |
