BATTERY CELL, COVER ASSEMBLY, BATTERY, ELECTRIC APPARATUS, METHOD, AND DEVICE

A battery cell, a cover assembly, a battery, an electric apparatus, a method, and a device are provided. The battery cell includes: an electrode assembly; a housing to accommodate the electrode assembly, where a wall portion of the housing includes a body portion and a fastener, the fastener is provided with a recess communicating with the outside, and the recess is arranged on an inner surface of the fastener facing the electrode assembly and recessed in a direction leaving the electrode assembly; and an air-permeable member covering the recess, where the air-permeable member is configured to allow gas to be discharged to the outside of the housing through the recess when a gas pressure inside the housing reaches a threshold, a bottom wall of the recess is provided with a protruding portion extending toward the electrode assembly, and the protruding portion is configured to be attached to the air-permeable member.