Battery casing for a motor vehicle battery

The invention relates to a battery case (10) for a motor vehicle battery, comprising an apparatus (12) for reducing an inner pressure inside the battery case (10) and a signaling device (20; 22; 28a, 28b; 30; 32; 36; 38a, 38b), wherein the signaling means (20; 22; 28a, 28b; 30; 32; 36; 38a, 38b) is adapted to at least one state of the device (12) for reducing the internal pressure to signal.