Battery impedance is a combination of internal resistance and reactance where internal resistance + reactance, or (L+ C), equals impedance when using an ac stimulus. The internal resistance of a battery is made up of two components: electrical, or ohmic, resistance and ionic resistance.

What is normal battery impedance?

The internal resistance can vary with things like battery age and temperature. In 10 minutes, the resistance value might be different! A common AA alkaline battery might have anywhere between 0.1 Ω and 0.9 Ω internal resistance.

How do I check battery impedance?

In simple words – the impedance is determined by an application of an AC current signal, measuring the AC voltage drop across the battery and then calculating the impedance by use of the Ohm's Law. As the battery gets older, the internal impedance increases.