By inserting Equation 8 into Equation 2 as the boundary conditions, Equation 1 can now be solved as the following by the Zero-Shift Theorem. 𝐶(0, 𝑡) = 𝐶 " + 𝐹(𝑡) -𝐻(𝑡)𝐹(𝑡 -𝜏 # ) 10 where C0 + F(t) is the full solution of Equation 1 when i(t) = I, shown in Equation . F(t -τ1) can be approximated by the semi-infinite diffusion case (t << L 2 /D) since the ICI method only analyzes the potential change in a short period Δt after the current is switched off, which means Δt = t -τ1 << L 2 /D. Thus, when t ≥ τ1, Equation 10 can be written as: