## 3 Results and Discussion
A more negative corrosion potential signifies enhanced electrochemical activity, as evidenced by the extended battery discharge time. Figure 2.1 SEM images and EDX mapping at the surface of the zinc-coated anode—(**a**) pure aluminum and (**b**) aluminum alloy 6061—using aqueous zinc solution containing EDTA during electrodeposition. The same tendency towards polarization curves occurred with the use of the aluminum alloy 6061 anode, as shown in Figure 2.2 The corrosion potential shifts to a more negative value in the order of AA 6061, Zn-AA 6061, and Zn(EDTA)-AA 6061. The higher negative corrosion potential led to better electrochemical activity. As shown in Table 3, the corrosion current density, \(I_{corr}\), increases with the zinc coating on the surface of the aluminum alloy, then is followed by the highest value of EDTA treatment during electrodeposition of the zinc alloy. The use of the 6061 aluminum alloy gives lower corrosion resistance compared to pure aluminum. The zinc-coated anode also decreases corrosion resistance and decreases most with EDTA treatment during the electrodeposition process, as shown in Table 3, indicated by the increase in the corrosion rate. In addition, the deposition of zinc on the 6061 aluminum alloy results in a discharge time that exceeds that of pure aluminum, as illustrated in Figure 10b. The zinc layer, with or without EDTA addition, plays a significant role in the extended battery life for the discharging process. The deposit of a thin layer on the surface of the anode prevents the instability of the metal-based anode, including dendrite growth, metal corrosion, and interference by heteroions [40; 41]. Figure 2.3 Polarization curves at scan rate of 10 mV.s\({}^{-1}\) of pure Al, Zn-pure Al, and Zn(EDTA)-pure Al in 3.5% NaCl solution. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Anode Sample**} & **Icorr** & **Ecorr** & \multirow{2}{*}{\(\alpha_{a}\)} & **Corrosion Rate** \\  & **(\(\mu\)A cm\({}^{-2}\))** & **(V, Ag/AgCl)** & & **(mm/year)** \\ \hline Pure Al & 2.18 & \(-\)0.912 & 0.323 & 0.025361 \\ Zn-pure Al & 16.16 & \(-\)0.983 & 0.332 & 0.13666 \\ Zn (EDTA) pure Al & 18.41 & \(-\)1.032 & 0.436 & 0.21395 \\ AA 6061 & 29.72 & \(-\)0.696 & 0.192 & 0.3454 \\ Zn-AA 6061 & 72.56 & \(-\)0.9466 & 0.252 & 0.84322 \\ Zn (EDTA)-AA 6061 & 110.59 & \(-\)0.9949 & 0.306 & 1.285 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Electrochemical parameters of anode samples. The discharge behavior in a 3.5% NaCl solution for pure aluminum anodes coated with zinc, with and without EDTA during electrodeposition, is shown in Figure 10a. This figure shows that the zinc coating leads to a more stable and prolonged discharge behavior compared to the scenario without the zinc coating. Specifically, zinc-coated pure aluminum anodes prepared with EDTA during electrodeposition exhibited a discharge duration of 72 h, exceeding the discharge time of 52 h of those prepared without EDTA, at a relatively constant voltage of 0.55 V. These findings are consistent with polarization measurements, which indicate that the incorporation of EDTA in the Zn electrodeposition process enhances electrochemical activity. The addition of EDTA during zinc electrodeposition on the aluminum alloy anode results in the longest discharge time, extending up to 207 h, almost double the duration of the anode prepared without EDTA, which lasts up to 124 h at a relatively constant voltage of 0.55 V. The use of EDTA-assisted electrodeposition for zinc thin films yields the optimal discharge performance of the battery. The modified anode with electrodeposition boasts a valuable improvement in comparison to the original anode. The lack of pure Al performance is caused by the oxide layer that was naturally formed. The oxide layer blocked the active surface to react with the electrolyte; therefore, the open circuit potential of the coated anode is higher than that of the initial anode. The oxide layer in coated Al is expected to be removed in a pretreatment process before electrodeposition.