BATTERY CHARGE - DISCHARGE ANALZYER

Battery-Supercapacitor TESTER  is a charge and discharger which measures the charge and discharge-time characteristics.

• Potentiostatic Constant voltage discharging measurement (DSC-CV)

• Galvanostatic Constant current discharging; measurement (DSC-CC)

• Constant power discharging measurement   

Technical specifications

Voltage setting: 0.00-30.00V

Voltage resolution:  0.01V 

Charge voltage: 18V

Dsicharge Current setting: 0.10-20.00A

Current resolution: 0.01A 

Charging current:  0.10-5.00A, 

Charge current resolution: 0.01A 

Automatic charge and discharge analysis

Charge-discharge-charge method

Battery capacity test

Voltage measurement:

Wiring method: four-wire detection, voltage measurement and current channel separate wiring to ensure measurement accuracy

SOFTWARE

USB  connection

Plotting curves

cycling charge and discharge, etc.

calibrating measurement 

System include

Battery-supercapacitor analyzer

Software

Connections cable

Bode and Nyquist Plot

In this chapter the two main ways of visualizing Electrochemical Impedance Spectra (EIS), the Nyquist and Bode plot, are presented and it is explained how different EIS of easy electronic circuits will be plotted in the Bode and Nyquist plot. This demonstrates the advantages and disadvantages of the two plots as well as serving as a foundation to understand the analysis of EIS by utilizing equivalent circuits.

As mentioned in the previous chapter there are two main ways to plot an impedance spectrum. One is the Bode plot. This plot is actually two plots in one. The abscissa is a logarithmic scale of the frequency and one ordinate is the logarithm of the impedance Z while the second ordinate is the phase shift Φ.

The advantage of this plot is that all information is clearly visible. A capacitor in parallel to a resistor, which is an important circuit for electrochemical impedance spectroscopy, is visible in this spectrum as a peak in the phase shift. Single components can be easier understood in the Bode plot.

The Nyquist plot is more complex to understand, but due to practical reasons is more popular in electrochemistry. One reason is that the Nyquist plot is very sensitive to changes. Another is that for the most common circuits some parameter can be read directly from the plot. To get a Nyquist plot the negative imaginary impedance –Z’’ is plotted versus the real part of the impedance Z’.

In the following paragraphs some simple components effects on a Bode plot and Nyquist plot will be shown. This is useful, because it is common to create an electronic circuit that represents the electrochemical system under investigation