| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a negative electrode for a nonaqueous electrolyte secondary battery, which can prevent a fallout of an active material from an active material layer. <P>SOLUTION: The negative electrode 10 has an active material layer 12 containing particles of an active material containing Si or Sn. A surface of the active material layer 12 is covered by a polymer film 14 having a plenty of hole portions through which an electrolyte solution can flow. The polymer film 14, when the negative electrode 10 is bent, has an enough elongation to maintain a surface covering status of the active material layer 12 by being elongated with the bending. Desirably, a porosity of the polymer film 14 may be 5% to 90% and the thickness 0.5 to 5 μm. The active material layer 12 contains particles of an active material containing Si or Sn and it is desirable that at least part of a surface of the particles may be covered by a metallic material 13 of a low lithium compound forming capability, and that gaps may be formed between the particles covered by the metallic material 13. <P>COPYRIGHT: (C)2009,JPO&INPIT |
