For large batteries such as those used in Power Stations, short circuit currents may exceed 40k amperes. Even when the battery is not fully charged, the short circuit current is very similar to the published value because the internal resistance does not vary substantially until the cell approaches fully discharged.
To recap: the short circuit current is a function of several variables but is mostly determined by the nominal voltage and internal series resistance. If the positive and negative terminals are connected by a wire then the battery is by definition shorted. What the voltage of the battery is does not really matter.
Practical considerations such as the effects of temperature, state of charge and type of circuit protection device are also presented. battery’s short circuit current is typically estimated by dividing its open circuit voltage by its internal resistance.
Estimated short circuit values can vary widely depending upon the test method and measurement technique. Multi-stepped discharge test methods that use a large span in current and voltage provide the best accuracy in estimating battery short circuit current and resistance.
By short circuit we mean an electrical short circuit, a very low resistance path between the positive and negative sides of the cell or cells. A short circuit can be inside a battery cell or external to a battery cell. There are a number of things that can cause an internal short circuit within a battery cell.
In comparison, the published short circuit current for a single cell is 6,150A. Consider a 2500 Ah cell having a published internal resistance of 0.049mΩ. This battery has 240 cells and the external circuit has a resistance if 21mΩ. The short circuit current is estimated to be:-