I was hoping to see if there was significant volt drop across individual cells when they were put under load.Finding info on the new Ioniq is very difficult, let alone any sort of diagnosing work, I could barely find good reviews on the car! What are you wanting to check through the OBD-II? Voltage or mAh? My question is even if you are able to connect to the car, how will you learn anything? Seems like it'd be necessary to have a before snapshot of the voltage or capacity, and then you could have a reference point to compare to?
I'm an engineer as well, so speak freely