Cyclic Charge-Discharge Experimental Sequence

Run the Cyclic Charge-Discharge standard technique by selecting Experiment>Electrochemical Energy>Cyclic Charge Discharge from the Framework™ menu bar.

NOTE: Based on your input, the sequence may change slightly. Options include starting with a charge step or discharge step; if Electrochemical Impedance Spectroscopy is available, you can add interleaved EIS scans. For this description, we assume that no EIS scans are done, and that the first step is a charge step.

This initiates the following sequence of events:

  1. The Framework creates a Runner window, and the pwr cyclic charge discharge.exp script is run in this window.
  2. The script creates the first Setup dialog box and accepts changes in the parameters.
  3. After you click the OK button, a second dialog box is displayed, containing additional parameters.

  4. The script now obtains the use of the potentiostat specified during Setup, and opens the data file specified in the Output name. The Runner window's Title reflects the Output filename. If the potentiostat is in use or the file cannot be opened, the script returns to the Setup dialog box.
  5. The file header information is written to the data file. This information is written to the file prior to data acquisition. If the experiment is aborted, the output file contains only this information. This header information includes: (a) Tags identifying possible analysis; (b) The current time and data; and (c) A list of setup parameters.
  6. The cell is turned on.
  7. The charge begins. Readings are taken at fixed time-intervals during the charge. The charge runs until either a stop criterion is met or until the maximum time specified in the setup parameters step. A plot of voltage and current versus time is displayed during the charge.

  8. If you specified a subsequent Voltage Finish in the setup parameters, a potentiostatic hold (performed galvanostatically with a software feedback loop) is performed. This hold runs until either the current falls below a specified level, or for a user-specified maximum amount of time.

    The data are displayed on the same voltage and current plot.

  9. The discharge begins. Readings are taken at fixed time intervals during the discharge. The discharge runs until either a stop criterion is met or until the maximum time specified in the setup parameters step.

    A plot of voltage and current versus time is displayed during the discharge.

  10. The data for the capacity curve are now calculated. Both a charge and a discharge capacity are calculated.

    A summary plot of cycle number versus charge capacity and discharge capacity is displayed.

  11. While neither the maximum number of cycles specified in the setup parameters step nor the loop stop at criteria are met, the sequence repeats beginning at step 7. If either the cycles or loop criterion is met, the sequence moves to step 12.

  12. The data are written to the output file, and the script cleans up and halts. After the experimental sequence is complete, the cell is turned off. The acquired data are written to the output file. The script then waits for you to click the F2-Skip button. After you do so, the script closes everything that's open, including the Runner window.