Resistance value of an aged cell

[MarcoZangrandi]

Hi, is there a variable with which I can identify the resistance value of an aged cell? I would like to do ageing cycles where I can see the decrease in capacitance due to ageing mechanisms and the relative increase in resistance. Thank you

[DrSOKane]

PyBaMM keeps track of most overpotentials. The file plot_voltage_components.py has a handy list of the variables you need:

        overpotentials = [
            "Battery negative particle concentration overpotential [V]",
            "Battery positive particle concentration overpotential [V]",
            "X-averaged battery negative reaction overpotential [V]",
            "X-averaged battery positive reaction overpotential [V]",
            "X-averaged battery concentration overpotential [V]",
            "X-averaged battery electrolyte ohmic losses [V]",
            "X-averaged battery negative solid phase ohmic losses [V]",
            "X-averaged battery positive solid phase ohmic losses [V]",
        ]

The electrolyte Ohmic losses and concentration overpotential will increases as the porosity decreases, so definitely keep track of those. The SEI also introduces an overpotential, which you can access as "X-averaged negative electrode SEI film overpotential [V]".