With STM and SEM, spherical partical electrode model was established for solving solid state ionic diffusion problem. A modified GITT method was introduced to estimate D to be 10^-^1^0 to 10^-^1^1cm^2.s^-^1. A partial charge ransfer across the interface was determined with XPS study and a kinetic equation was given. The model was applied to ClO~4^- intercalation into polythiophene. Coincide with the semiconductor property, the exchange current of deintercalated polythiophene was very low while α+β<1. It further proved the partial charge transfer model.

Key words: DYNAMICS, HIGHPOLYMER, DIFFUSION, LITHIUM, THIOPHENE, MODELS, INTERCALATION REACTION