Battery acid is highly corrosive
WARNING: This page does not describe the selected car, but rather 14 other vehicles, including the 2011 BMW 328xi, 2011 BMW 328i, 2011 BMW 323i, 2010 BMW 335xi, and 2010 BMW 335i. However, it is still accessible from the selected car via links, so may be relevant.
Do not allow any battery acid to come into contact with the eyes, the skin or clothing. Therefore wear protective clothing, gloves and goggles.
Do not tilt the battery, acid may emerge from the vent opening.