An external short circuit can occur if the battery terminals are connected by any type of conductive material. Depending on the battery system, a short circuit can have serious consequences. Lead-acid batteries are very powerful and a short circuit can cause burns, fires or an explosion of the battery.
Never connect the positive pole of the battery to its negative pole. When installing the battery, or when attaching the connecting cables to the battery poles, take all necessary measures to avoid short-circuits caused by tools or other conductive materials.