How does metallic bonding allow metals to conduct electricity?

In materials science, the electrical conductivity of metals is primarily attributed to the nature of metallic bonding. In a metallic solid, atoms are closely packed, and their outermost valence electrons are not bound to any specific atom. Instead, these electrons become nonlocalized, forming a "sea" or cloud of mobile charge carriers that move freely throughout the entire crystal structure.123

Because these valence electrons are not associated with any particular atom, they are highly responsive to an electrical field. When a potential difference is applied, these free electrons can easily migrate through the lattice, facilitating the flow of electric current.143

While the presence of these mobile electrons is essential, a metal's actual conductivity also depends on the mobility of the electrons—the ease with which they can be pulled through the solid—and the purity of the material, as impurities can introduce irregularities that interfere with electron movement.4