3 Applications
Overview
State of charge
(Li-Ion, Lead)
Nyquist plot
(Spectral
impedance)
Operational behav-
iour, Beschädigun-
gen, Modellparame-
ter
Qualificati-
on and
exchange
Data sheet
or initial
measure-
ment
First steps, typical approach
It is good practise to take the following approach for characterising batteries:
Measurement of the open circuit voltage (OCV). The acceptable range can be
taken from the specifications or from the discharge curve.
The menu “Diagnosis” uses typical values which are stored in a spreadsheet,
from which the SoC can be derived.
Measurement of the AC resistance (R
AC
, ESR). In the menu “Single impedance”
choose the standard frequency 1kHz and compare it with the specification.
The function „Diagnosis“ uses this parameter to estimate the ageing (SoH) by
comparing this value with a reference value, which has to be defined once.
For determining the operational behavior measure the DC impedance at 0,5Hz
and compare it with a reference value from a new battery.
For deeper analysis measure the Nyquist plot and compare it with the plot of a new
battery.