Battery EIS Testing Issue with CN0510

Hi ADI Team,

I have been evaluating the CN0510 using the ADICUP3029 board for battery EIS testing. Initially, I was able to obtain the expected Nyquist curve, as shown in Fig. 1. However, I recently encountered an issue where I can no longer reproduce the correct Nyquist curve under the same setup and battery, as illustrated in Fig. 2.

I have already checked the wiring connections and verified the ADICUP3029 firmware, but I haven't found any obvious problems. Do you have any suggestions on how I can further debug this issue?

Figure 1

Figure 2