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