An alert system for an electronic housing, including: a gas property sensor, wherein a processor is configured to receive gas property data from the gas property sensor, and configured to determine a property of a battery included in the electronic housing; a degassing unit for attaching to the electronic housing and configured to enable passage of gases and to prevent passage of liquids and solids, the gas property sensor being attached to the degassing unit at an inner side. A degassing unit comprising a base comprising an attachment means for fluid-tightly attaching to a venting opening of the electronic housing and an opening covered by a semipermeable membrane thereby forming a gas passage; a sensor module including a gas property sensor, the sensor module attachable to the base on an inner side of the base, the sensor module extending away from the semipermeable membrane towards a direction substantially perpendicular to the semipermeable membrane.