| 摘要 |
PROBLEM TO BE SOLVED: To maintain a high discharging capacity by arranging active material particles so as to be distributed to have a large average particle size in the surface side of an electrode mixed layer and a small average particle size in a collector sheet side, and forming a continuous phase in the thickness direction of the electrode mixed layer by binder. SOLUTION: An electrode sheet is composed of a collector sheet and an electrode mixed layer including active material particles and a binder formed in the surface of at least one side of the collector sheet. The electrode active material particles are distributed to be large in average particle size in the surface side of the electrode mixed layer and small in the collector sheet side. The electrode mixed layer of the electrode sheet is arranged such that the active material average particle size has a gradient in the thickness direction of the electrode mixed layer, and a layer stage is formed and maintained by the binder for forming a continuous layer in the thickness direction. Thus, the physical strength of the entire layer is increased, the movement of lithium ions in a positive electrode mixed layer is made smooth and various ill effects are prevented. |
