To solve such a problem that a resin binder is easy to cause segregation in the vicinity of a surface of a mixture layer of an electrode, and thereby an electrolyte is prevented from penetrating inside the mixture layer, accordingly causing deterioration of load characteristics of a lithium ion secondary battery.
An electrode having a mixture layer in which a binder is substantially uniformly distributed as a whole can be configured by removing a segregated part of the binder formed on a surface of the mixture layer. Thereby, even when the mixture layer of the electrode is increased in film thickness for increased capacity or the like, an electrolyte is easily impregnated inside the mixture layer, so that the reactivity of the electrode is improved. Accordingly, a lithium ion secondary battery excellent in load characteristics can be configured.
Takao Matsuyama
Go Sakane
Tadashi Takezoe