摘要 |
To provide a means for sufficiently utilizing a high capacity characteristic of a solid solution positive electrode active material and capable of achieving satisfactory performance of a rate characteristic in an electrical device such as a lithium ion secondary battery containing a positive electrode using the solid solution positive electrode active material. An electrical device has a power generating element containing a positive electrode in which a positive electrode active material layer containing a positive electrode active material is formed on a surface of a positive electrode current collector, a negative electrode in which a negative electrode active material layer containing a negative electrode active material is formed on a surface of a negative electrode current collector, and a separator. The coating amount of the negative electrode active material layer is from 3 to 11 mg/cm 2 , and the negative electrode active material layer contains a negative electrode active material represented by formula (1) . The positive electrode active material layer contains a positive electrode active material (solid solution positive electrode active material) represented by formula (2), and a material represented by formula (3) and having a predetermined amount of a predetermined element M on particle surfaces is used as the solid solution positive electrode active material contained in the positive electrode active material layer. |