Answer：External short circuits can be caused by connecting the outer ends of the battery to any conductor. Depending on the type of battery, short circuits can have consequences ofvarying severity. For example, the temperature of the electrolyte will rise and the internal air 
pressure will increase. If the air pressure value exceeds the pressure resistance value of the battery cap, the battery will leak. This situation can seriously damage the battery. If the safety valve fails, it may even cause an explosion. Therefore do not short-circuit the outside of the 
battery.