Vacuum bottle for electrical switching device

An electrical switching device, comprising at least one vacuum bottle intended for the electrical switching device, including a cylindrical body of insulating material closed at each end respectively by a first metal cover and a second metal cover, the vacuum bottle including a mobile electrode that passes through the first cover and that cooperates with a fixed electrode between a closed position in which the mobile electrode and the fixed electrode are in contact with each other and an open position in which the mobile electrode and the fixed electrode are separated, wherein the second cover corresponds to the fixed electrode of the vacuum bottle and includes projections intended to be connected directly with a busbar belonging to a pole of the electrical switching device, wherein the second cover includes a central fixed contact zone having a shape of a spherical cap turned towards an inside of the vacuum bottle, wherein the mobile electrode includes a mobile contact zone of rounded shape situated facing the fixed contact zone and wherein the fixed contact zone presents a curve radius greater than that of the mobile contact zone,

• the vacuum bottle being placed as derivation of a main circuit of at least one phase of the electrical switching device.