| 摘要 |
In cases where a material containing silicon is used as a negative electrode active material for lithium secondary batteries, adhesion between a mixture layer and a collector is insufficient and thus current collection performance is decreased by expansion and shrinkage, thereby decreasing the cycle characteristics. This negative electrode is characterized by being provided with a collector, a first mixture layer containing first active material particles and a binder, and a second mixture layer containing second active material particles and a binder. This negative electrode is also characterized in that: the first mixture layer is arranged on the collector; the second mixture layer is arranged on the first mixture layer; the first active material particles and the second active material particles contain Si; the second mixture layer is provided with a columnar part; the expansion ratio of the second mixture layer during the charging period is larger than the expansion ratio of the first mixture layer during the charging period; and the electrical conductivity of the first mixture layer is larger than the electrical conductivity of the second mixture layer. |
