VS - Electrical Systems From Stop-Start to Hybridization

Internal Resistance Batteries are not perfect voltage sources; they embed an intrinsic “weakness”, their internal resistance (Ri). The internal resistance is a source of losses that is proportional to the current demand, the value of this resistance is not constant, it fluctuates according to temperature and to battery aging. Heat lowers Ri value and cold raises it. Measured in milliohms (m Ω ), the internal resistance acts as a limiter inside the battery; the lower the resistance, the less restriction to supply energy. Sulfation and grid corrosion is the main contributor to the rise of the internal resistance with lead acid batteries. As the internal resistance increases, the battery efficiency decreases and thermal stability is reduced as more of the charge and discharge energy is converted into internal heat.

Ri

Ri - The Internal Resistance is a restriction to current flow

Restriction on supplied power

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