We started with a symmetric cell built with lithium-ion electrodes and a composite polymer electrolyte . The impedance was modeled with a 3 × ZARC whose parameters were estimated by RR (see Table for the values of these parameters). Given 𝑁 = 10 𝑀, Figure presents the recovered DRT and impedance, while Figure shows the plots of the impedance modulus and argument. Regarding the DRT, the peaks at 𝜏 = 1 s and 𝜏 = 1.91×10 -4 s were well identified. However, the peak at 𝜏 = 1.05 ×10 -7 s was not recovered because the corresponding dispersion factor 𝜙 was equal to 1 (Table ). This explains the high DRT error for RR (𝜀 , = 44.17% for all 𝑁, see Table ), which was greatly reduced after DNN training (𝜀 , ≈ 26.17%). The same conclusion can be made for the impedance recovery (𝜀̅ , = 9.30% and 𝜀̅ , ≈ 6.09%, see Table ).