DCIR - Direct Current Internal Resistance
Direct current internal resistance (DCIR) of batteries is the r esistance of current flowing through the battery, with the standard unit of measurement called the ohm.The value of DCIR is not fixed, and varies depending on multiple factors, such as battery materials, electrolyte concentration, temperature, and depth of discharge.
The variation of DCIR has a great influence on battery discharge performance, especially for high power batteries. In general, the better the battery, the lower the internal resistance. Therefore, most battery manufacturers identify DCIR as a key indicator to evaluate battery quality. The method of DCIR measurement is to inject high current into the anodeand cathode of the battery in a short period, and then record the changes of battery voltage and charge/discharge current. To calculate DCIR by Ohm’s Law, voltage variation is divided by current variation.
IEC 61960 - for Portable Applications
DCIR - HPPC or other simliar method for EV
DCIR method for EV is largely varied from those basic method for portable applications. Unlike only discharge DCIR is considered for those portable applications, DCIR for EV batteries has also charge DCIR. Specially, SOC related DCIR values are obtained to run simulation and for other uses. HPPC is a basic guidline for this. Moreover, ISO 12405-4:2018 developed this further with different pulse time.- Download Demo Data