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A.2 Frequency domain calculations
The following calculations were used to estimate the frequency response of a cell after
fitting the step response. Calculations are performed in the Laplace domain.
Z(s) = (R1+sL)∖∖Rm∖∖^-
sC
_ / sLRm ÷ R1Rm x I ! 1
^ l ∕2m÷jR1+sL )⅝C
Γ Rm Rl "∙" sɑ(sLRm + R1 Rm ) ^1 — ɪ
sLRm + RiRm sLRm + R1Rm
P s2 LRmC ÷ sCR1Rm ÷ sL + R1 + Rm -,ɪ
sLRm + R1Rm
s2LRmC + s(CRιRm + L) + R1 + Rm
s L Rm + R1 Rm
Z(s)≈