The present application provide a connection component, a battery cell, a battery, and an electric device. The connection component includes a body, a convex portion, a concave portion and a gap control portion, and the body includes a first surface and a second surface opposite to each other in a thickness direction thereof; and the gap control portion is configured to be when the associated connection component is stacked on the other connection component, said gap control portion is in contact with said the other connection component, so as to control a dimension of a gap D between the two connection components to be greater than 0.6H, wherein H is the height of the convex portion protruding from the first surface. According to the connection component provided by the present application, the gap between two adjacent connection components can be controlled when material is stuck.