## 3 Results and Discussion
\begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline
**Cycle\textbackslash{}Cell** & **A1** & **A2** & **A3** & **A4** & **A5** & **A6** & **A7** & **A8** \\ \hline
1 & 100 & 100 & 100 & 100 & 100 & 100 & 100 & 100 \\
100 & 95.93 & 97.16 & 97.42 & 97.48 & 98.41 & 97.93 & 98.11 & 97 \\
200 & 95.35 & 96.65 & 96.23 & 95.94 & 96.21 & 96.19 & 96.91 & 96.14 \\
300 & 93.65 & 94.42 & 94.92 & 94.27 & 94.8 & 94.95 & 95.06 & 94.03 \\
400 & 91.64 & 92.08 & 92.72 & 92.15 & 93.43 & 92.86 & 93.57 From Figure 3, it is evident that the differences between the experimental SoH and estimated SoH vary over their lifetime for the tested cells. The estimation differences are higher for cycle numbers from 1 to 60. The rapid degradation of SoH from 1 to 60 cycles is likely to be attributed to the transformation of the hexagonal structure to a cubic spinel structure of the electrode which occurs via an intermediate phase as observed previously by [PERSON] et al. [15]. To further validate our ECBE model results, we have also added the Coulomb counting result in Figure 4. However, it was mentioned in the introduction that there are many disadvantages to employing the Coulomb counting method, as mentioned by researchers. Coulomb counting employs an open-loop estimator, which generates larger cumulative errors. It also does not take a change in the battery's capacity into account as the battery ages [30]. Other disadvantages of the open-loop are its sensitivity to the current sensor precision and uncertainty of initial SoC [31]. It also shows an increase in charge at certain cycles, as observed during the ECBE charge estimation results. The higher value of Qm over Qd is expected, as explained in [PERSON] et al. 's work [15]. A very interesting point is observed from Figure 4 regarding the charge increase at various aging cycles. This is an unusual phenomenon observed in our results, and we would like to investigate it further by performing a charge cycle-dependent test for batteries. This will be our future work, and we would hope to share our findings from our test with the scientific community very soon. Figure 3: State-of-health (SoH) estimation curve for cell A2 to compare the difference between experimental SoH and estimated SoH. \begin{table}
\begin{tabular}{l c c c} \hline \hline
**Cell\(\backslash\)K-Value** & **k1** & **k2** & **k3** \\ \hline A1 & \(-3.28\times 10^{-7}\) & \(1.779\times 10^{-4}\) & 0.013339 \\ A2 & \(1.73\times 10^{-7}\) & \(1.21\times 10^{-4}\) & 0.012944 \\ A3 & \(9.71\times 10^{-7}\) & \(-3.64\times 10^{-5}\) & 0.0241156 \\ A4 & \(1.24\times 10^{-7}\) & \(1.87\times 10^{-4}\) & \(-0.0081339\) \\ A5 & \(7.39\times 10^{-8}\) & \(1.81\times 10^{-4}\) & \(-0.00796576\) \\ A6 & \(2.63\times 10^{-7}\) & \(9.98\times 10^{-5}\) & 0.00652144 \\ A7 & \(1.97\times 10^{-7}\) & \(5.15\times 10^{-5}\) & 0.025597 \\ A8 & \(2.38\times 10^{-7}\) & \(2.19\times 10^{-4}\) & \(-0.0092757\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: The parameters of k1, k2, and k3 are calculated from the SoH formula. To probe further into the differences in the estimation to investigate the usefulness of the model for SoH estimation, a comparison of the differences between the estimated and experimental SoH over the battery lifetime was performed.