Calculated Quantitites

Some data available in the Gamry Echem Analyst™ are not present in the data file, but are automatically calculated by the Analyst when the data file is loaded. The quantities that are calculated depend on the type of data file loaded. Not all analysis scripts calculate all quantities.

Some quantities are present in certain types of data files but are calculated by the Analyst in others. For example, energy is present in Cyclic Charge-Discharge data files but is calculated by the Analyst for other file types.

Capacity/Charge Calculated as the sum of current multiplied by time. You have the choice to display this as the Capacity field with units of ampere-hours or Charge field with units of coulombs. (See script-specific Options)
Energy Calculated as the sum of power multiplied by time. Unit is watts.
Load Resistance Calculated as voltage divided by current. Unit is ohms.
% Capacity Calculated as 100 × Charge / Nominal Capacity using the nominal capacity value entered during experiment setup. This value can also be recalculated using the Recalculate % Capacity button.
Capacitance Calculated as charge divided by the change in voltage. Units is farads. For Cyclic Charge-Discharge data files, this quantity is calculated for each step, resulting in a new data column. For all other type of data files the calculation is performed on demand and results in a single value (See Calculate Capacitance).
Coulombic Efficiency (For Cyclic Charge-Discharge only.) Calculated as the ratio of the charge in the discharge step versus the charge in a charge step for each cycle.
Energy Efficiency Calculated as the ratio of energy obtained in a discharge step versus the energy lost in a charge step for each cycle.
Real Time

This quantity is only calculated for Charge and Discharge data files, and is only relevant when those files were generated as part of a Cyclic Charge-Discharge experiment (See Save Raw Data). The Real Time values represent the time elapsed from the beginning of the Cyclic Charge Discharge experiment, as opposed to the column for time (T), which represents the time elapsed from the beginning of the charge or discharge step. By overlaying multiple charge and discharge plots and selecting the Real Time using the curve selector, charge and discharge plots can be shown in chronological order along the x-axis instead of the plots overlaid on top of each other all starting at zero seconds. The image below shows several successive change and discharge plots with real time displayed on the x-axis .