CASING, BATTERY CELL, BATTERY, AND ELECTRICAL APPARATUS

Embodiments of the present application provide a casing, a battery cell, a battery, and an electrical apparatus. An opening is formed in the casing; the casing comprises a first wall and at least one second wall that are opposite to the opening, and the first wall and the second wall intersect with each other; the first wall and the second wall are connected by a first fillet, and the inner diameter r1 of the first fillet and the minimum thickness T2 of the second wall with the minimum thickness among the at least one second wall satisfy: 2.0 ≤ r1/T2 ≤ 30; the yield strength of the casing at the temperature of 25 °C is Re, wherein Re satisfies: 140 MPa ≤ Re ≤ 1000 MPa. According to the casing, the battery cell, the battery, and the electrical apparatus in the embodiments of the present application, the processing difficulty of the casing and the spatial capacity and strength of the battery cell can be balanced.